I don't know anything about this site, but I just came across it, so I thought I'd share:
It's Book a Band
Here's what they say:
How does it work?
You can join Bookaband.com's online database of hundreds of bands for free at anytime. Once your band is accepted, it will become instantly visible to booking customers (organizers of events, weddings, festivals, clubs, etc.). Bookaband.com is a booking agency and as such, we work on a percentage basis. If someone chooses to book your band, we will notify you immediately and discuss the details.
How do I get started?
It is simple, fast, and free to get published on Bookaband.com. And since there is no subscription charge and no sign-up fees, you really have nothing to lose. All you have to do is to create an account and upload your band's media (bio, picture, setlist, mp3s).
We don't have mp3's. Can we still sign up?
Yes you may. But keep in mind that keeping an up-to-date bio, photo, setlist, and adding sound samples (mp3s) will substantially increase your chances of receiving an inquiry. We highly recommend that you provide us with all the information possible.