I heard that "Black Rock Shooter" originated as just a picture, but was later made into a song by the Vocaloids (Courtesy of Miku Hatsune). And now it's being made into one of the most anticipated anime OVA's of the summer.
But does anyone know where to find the original pic that started all the hype?

Its wan't a pic, it was the song, that got it all started.

Cuda's right:

Black Rock Shooter was a song by Ryo (the main guy behind Supercell, of Bakemono ED fame, and a bunch of other Vocaloid songs.) It was made before he got picked up by Sony Music group (and therefore supplied an actual vocalist.)

Part of the thing about Supercell was the artwork that was made by the group. (The vast majority of Supercell is actually supporters and illustrators. Only Ryo handles music. Not sure about the arrangement now, since he got a vocalist under the Supercell name. His vocaloid stuff is attributed as "ryo".)

The BRS Char (now kuroi_mato) was created by huke, a fellow Supercell supporter/member, for the song.

After that, it was left to the fandom and BRS went the way of Miku and the other Vocaloids. BRS's resemblence to Miku might've had a helping hand though. (I think I read someplace that the BRS image was inspired by what huke thought a dark Miku coulda been like.)

Thanks for the clear up guys...or girls...you can never really tell on the net. (<_<)

No worries. If I was a girl, I'd be a lesbian anyway...^_~