Search Engines are a highly effective way to promote your site. To get a good search engine ranking you will want to add meta tags to your pages.
You can use the meta tag wizard at Bravenet or write your own. They also Have a Meta Tag Checker at Bravenet which is very helpful see resources for details.
Next you will need to submit your url to the search engines here are a few to get you started.
Although these are an option and some people swear by it most banner exchanges I have tried honestly suck. My site displayed hundreds of banners while my click through rate was nil. Private exchanges with people who have content related to your site work much better, as does reciprocal linking.
I have had some nice results with web rings. I find them far superior to banner exchanges. Not all rings are created equal so shop around. One of my web rings at my 3d site accounts for more then 50% of my traffic. Literally thousands of hits. If your running any kind of art related site I recommend it highly Renderosity Web Ring. So far that one has worked best for me.