Major/unique promotional techniques.

Brochures or flyers.
Direct mail.
E-mail messages.
Magazines.
Newsletters.
Newspapers (major).
Newspapers (neighborhood).
On-line discussion groups and chat groups.
Posters and bulletin boards.
Radio announcements.
Telemarketing.
Television ads.
Web pages.
Yellow Pages.
Articles that you write.
Editorials and letters to the editor.
Press kits.
Press releases or news alerts.
Public service announcements (PSA)s.

Yah, some can appear to be pricey but with the right method and target audience it will be worth it and benefit you and your site.