my meager contribution:
The Buzzcocks, The Damned, Violent Femmes, Big D and The Kids Table, Big Rude Jake, The Brian Setzer Orchestra, Jerry Jerry and the Sons of Rhythm Orchestra, Cracker, Reverend Horton Heat, The Faces, Fury In The Slaughterhouse (the music is better than the name, I swear), Lordi (not really for everyone, either you enjoy them and all of their goofiness or you just can't get into it, not much middle ground), The Mooney Suzuki, Oysterhead, The Presidents of The United States of America, The Pogues, The Replacements, Rheostatics, The Specials, The Watchmen (no, Rorschach is NOT part of the band), aaannnnnd The Purple Gang.
I have no idea if any of the bands are really unknown or not, since I pay NO attention to what people listen to. Anyway, hope I helped.