Found my way here from MrDood's link in Trollhearts
thread and couldn't help but be intrigued by the idea. Admittedly a couple of these are just the only band I could find from a state that I even kind of like, but I guess that still makes them my favorite from that state

.
Alabama - Remy Zero
Alaska - Portugal The Man
Arizona - Lydia
Arkansas - Johnny Cash
California - Tool
Colorado - Chairlift
Connecticut - MGMT
Delaware - BoySetsFire
Florida - Marilyn Manson
Georgia - Baroness
Hawaii - Israel Kamakawiwo'ole
Idaho - Built to Spill
Illinois - Smashing Pumpkins
Indiana - Murder By Death
Iowa - Raccoo-oo-oon
Kansas - The Anniversary
Kentucky - Slint
Louisiana - MUTEMATH
Maine - Big Blood
Maryland - Lungfish
Massachusetts - Converge
Michigan - The White Stripes
Minnesota - Eyedea
Mississippi - Colour Revolt
Missouri - White Rabbits
Montana - David Lynch
Nebraska - the Faint
Nevada - Curl Up and Die
New Hampshire - Will Sheff
New Jersey - Danzig
New Mexico - Beirut
New York - Sonic Youth
North Carolina - Corrosion Of Conformity
North Dakota - godheadSilo
Ohio - Mr Gnome
Oklahoma - Other Lives
Oregon - Grails
Pennsylvania - Trent Reznor
Rhode Island - Sage Francis
South Carolina - Band of Horses
South Dakota - Examination Of The…
Tennessee - The Dead Weather
Texas - At The Drive In
Utah - Gaza
Vermont - The Cancer Conspiracy
Virginia - Denali
Washington - Modest Mouse
West Virginia - Zao
Wisconsin - Zola Jesus
Wyoming - Teenage Bottlerocket