Advertising your site for selling, starts with the planning of site creation. First and most Important step is Knowing exactly who your market will be. Besides being optimized for SE's, your site should contain compelling ad copy.
When site is ready, first thing is to submit site to the Major search engines. If you don't own a specialized software for this, be sure to submit it manually to each engine.
Submitting to directories related to your target market is a good free way of getting some quality traffic. Be sure to use very good ad copy and some keywords in your description, but don't repeat keywords. The same applies when submitting to PPC's and any other places requiring site description.
Joining and participating in newsgroups that your target market belong to, is another good free form of advertising.
As DC has mentioned, add your signature for forum posts, emails and newsgroups, etc.
Don't waste your time and site space on free banner exchange services. If you do exchange banners, it's best to do so with selected relevant sites so you're assured that your banner is at least being seen by those whom you're targeting. You can even get quite a bit of targeted traffic by just having your banner on just One busy relevant site. Link popularity in general, is starting to get old, as SE's continue to get more intuitive.
Speaking of time, mine has run out here. Maybe some others will add some more tips.
Good luck!
