Really the best way is to come up with some content people will be interested in. What are the most appealing pages on your site ... the ones you want "deep" links to? Put links to those pages in forums, blogs, and such related to that. Also try del.icio.us, digg, and sites like that. Once people see good content, some of them will email the URL to a friend, some will mention it in their blog, some will put it on their links page...
The main purpose of my site is showing off my photography, but I've written a few articles ( example: Digital Black and White Conversions in Photoshop ), have mentioned them in a couple of photography forums, and they've generated a little bit of interest.
