I've mentioned before that one of the best ways to improve your website's search engine rankings is to get links from other sites. As a matter of fact, "link building" is one of the most important, and difficult parts of online marketing. It's a topic too large to tackle in one post, but luckily there's a pretty easy way to get started.
There are a number of services online called "directories" which are basically just huge lists of links to other websites. It's like the yellow pages but for websites. Submitting your site to a few directories can be a great way to generate a few incoming links.
There are all kinds of different directories out there, and you should probably do a Google search to find directories focused on your specific industry, but here are three major directories that you can start with:
DMOZ Open Directory Project - http://www.dmoz.org/
This is a massive directory with millions of different sites. It's free to submit your site, but because it's free they're not very responsive when it comes to reviewing your site. I've had varied levels of success with DMOZ, but it's definitely worth spending the time it takes to submit your site.
Yahoo! Directory - http://dir.yahoo.com/
This is another huge directory which is managed by Yahoo, but syndicated all across the web. It's much better run than DMOZ, but it costs $300/year to list your site. I'm not sure if it's worth the money, but most SEO advice I've read says that it is worth it. Basically, if you've got a reasonable SEO budget, submitting to this directory is probably a good idea. Otherwise, you might want to skip this one.
Technorati - http://technorati.com/
This directory is only for blogs (you do have a blog, right?) but it can be a serious source of traffic and inbound links. Technorati's website is incredibly frustrating and you'll probably want to take a sledge hammer to your computer during the website submission process, but it's worth the headache. I promise.
So those are the big three that I'd start with, but like I said, there are many more directories out there. I should warn you that if you're serious about SEO you'll need to get links from places other than directories, but this is an easy starting point to help you build momentum.