How to get your site more popular
Before you begin reading, I need everyone to know that I'm still not sure exactly what it was that I did to make A-U's popularity climb. Therefore, the following are things that can possibly help, but none of them by themselves will make your hits increase by 100% ;)
Have a site worth visiting
I know this is pretty obvious, but it's the first thing you have to realize: unless you have entertaining, unique, intriguing content, you won't get much traffic. If your site is a conglomeration of content from other sites and has a non-original template layout, not many people are going to remember your site as something special. It's hard to find something new when almost all the ideas have been taken, but start small. Make sure you make your own layout, for one thing. If your site has a template layout (for example, the green leafy Freewebs one is extremely overused, and you can only do so much with the default MSN groups layout), visitors will confuse your site with others. Try to make the layout yourself, too: don't have one made for you. It may be hard to start, but visitors will be impressed by your own skills.
On the subject of graphics, it's very important to learn how to make these well. A lot of sites claim to be graphic-makers; a small minority of them actually make professional-looking graphics. Learn how to blend and design graphics well and visitors will remember your work. Once you've learned, you can move on to making original banners, wallpapers, avatars, icons, and even rarer graphics that not many sites have, such as buttons, bookmarks, calendars, etc.
One of the main incentives for not stealing content from other sites is that if people have already seen your content on the original sites, they won't be very interested in looking at it again. Sure, you may get a few people who never saw the original source of the content, but most people will have seen it already. You can take ideas from other sites, but try not to copy exactly. Read different cast and character biographies to gain enough information to write your own; look at different graphic designs for ideas (but NEVER copy an idea exactly: I've had this happen, and it's downright plagiarism); look at source codes to see how other sites have used HTML and other codes to build their sites.
Have a memorable title and URL
One of the key aspects to having a popular web site is making it easy for people to remember your site. We've already talked about making original layouts and having original content, but another vital part is having a memorable site title and URL. If you're just now making your site, look around the web at different sites' links pages. Which titles/title themes do you see the most? Some overused titles are Middle-earth, Lothlorien, Imladris, and Lord of the Rings something. Avoid titles like these; also avoid titles that are place names in Middle-earth, since these are all overused as well. Don't make your title more than about four words, since longer titles are hard to remember. When you've come up with good title, google it (in quotes!) and see if there are any other sites that have already claimed it.
The URL is also important. If possible, you should buy your own domain name (http://www.yoursite.com), but even if you can't afford one, you can help visitors remember your URL by getting a free "domain name" from CJB.net (your URL will be yoursite.cjb.net) or Dot.tk (your URL will be yoursite.tk). Another option is to find a big LotR site that hosts other sites for free. Make sure that the site says on its web site that it's willing to host other sites before you ask! If you reach an agreement, your URL will probably be yoursite.theirsite.com. The one thing you DON'T want to do is have a URL so long or complicated that no one can remember it without writing it down. Make sure your URL also mirrors your site: if your site's title is "Minas Morgul", your URL should be something like http://www.minasmorgul.tk, not http://www.iluvlotr.tk.
Have lots of "linkware"
"Linkware" usually refers to programs/fonts that you're allowed to use only if you include a link back to the creator's web site. In this case, it refers to anything that you can post on your web site and have people link back to your site. Make banners and (if you have enough bandwidth) post codes below them so that people can put the banners on their sites, but so the banners automatically link back to your site. Do the same with any other graphics you want people to be able to put on their sites. Make it easy for people to purposely link to you by putting the codes for your link-back buttons under them. If you make things like brushes, ask people to link back to your site if they use them.
Affiliate/Add your site to links pages
Find the biggest LotR sites (and non-LotR sites, if they say they accept affiliates of all sorts) and ask if they want to affiliate. Make some 100x35 link-back buttons too. You won't always get that much traffic, but if people see your site's button everywhere, they might be intrigued and end up visiting.
Nominate yourself for different awards. You'll get traffic once you're up on a nominee list. If you win, people will click on your site from the awards site to see who the winner turned out to be, and with the awards you'll become more respected. Even if you don't win, you'll still have the visitors you got while you were on the nominee list.
Submit to toplists
The main toplist used to be Tolkien Top 100, and it used to be one of the main ways sites attracted visitors. It shut down over a year ago, but there are still many LotR and non-LotR toplists out there. Check out your fellow LotR sites to see what they've signed up for. Once you've signed up your own site, don't be afraid to ask visitors to vote for you: the higher you get on the toplist, the more prominent your site will be.
Make your site interactive
"Interactive" doesn't necessarily mean forums, chat rooms, and tag-boards (see the next section for that). All it means is that you let your visitors become as much of a part of your site as possible. Have a fan section: people can submit their work and see their names on the internet. Have polls: people can vote their opinions and influence the results. Have graphics requests/dedications: people can request graphics of certain characters and have their names on the graphics. Take suggestions and use them, crediting the people who made the suggestions. The more you involve visitors, the more they'll come back.
Have a strong community
Tag-boards, chat rooms, and forums all are good ideas. If you can establish a community where people make friends with other visitors and keep coming back to talk, your traffic will go up. Keep things friendly and welcoming, and try to have moderators around as much as possible. Make yourself a common presence too so that people can interact with you.
Become a presence on other sites
Although this is usually overlooked, it's pretty important when you're just starting out. You need to become a presence on other sites, especially big ones. Join their forums: you'll usually have room for a signature, where you can put a link to your site. The forums will usually have boards for members to post links to their sites, too. Also, if you become a familiar face on tag-boards, you'll usually have a place to put a link to your site. A bit of advice, though: NEVER, EVER spam message boards. Don't start a whole new thread out of place to tell people about your site, and don't post on tag-boards expressly saying "Vist my site! Visit my site!" Also sign guestbooks: they usually include text boxes to put your site's URL. Some of A-U's first visitors were from the Barrowdowns guestbook, which I had signed.
There's no substitute for this. If there isn't something new on your site, then unless you have a large community, people won't come back often. Try to update at least once a week, and you'll retain visitors.
Submit to search engines and link directories
This is probably one of the best ways to get traffic. If someone searches for an LotR-ish term and your site comes up on the first page, you have a very good chance of getting a lot of traffic. Remember to add META keywords and descriptions to your site! META keywords are used by a lot of search engines. Google, the main one, doesn't use those keywords: instead, they look at words in bold and italics on your page as keywords, as well as how often a word appears. They also look at how many sites link to yours, and how popular your site is. To get yourself listed, go to The Open Directory Project and enter your site under a LotR-related section: Google uses ODP to update their listings. Also look for LotR directories, such as ULOTRWD, and submit your site to them. The more prominent your site is, the more popular it will get.
So...that's basically it! Good luck, and enjoy your newfound popularity!