Aerosmith
Frank Marino and Mahogany Rush
NIN (paid $7.50 to see TR play his solo gig at a hole in the wall before he became famous)
Blue Oyster Cult (many times)
Rush (3x)
Peter Frampton
J Geils Band
Rick Derringer
Kansas
Night Ranger (at least 10 times, my wife is a huge fan and has seen them 90+ times)
Whitesnake
Peter Gabriel
Thomas Dolby
Police
Bananarama
English Beat
Thompson Twins
Velvet Revolver
AC/DC
Motley Crue (numerous times)
Van Halen (5 x including twice before Dave left, 2 x with Sammy, and once after Dave rejoined)
Bon Jovi (3)
Ratt (2)
White Lion (2)
Sting
Steve Perry
Krokus
Meatloaf
Deep Purple
Ozzy
Def Leppard
Cinderella
Bulletboys
Skid Row (many times)
Winger
April Wine
Bad Company
Foreigner (back when Lou Graham was still singing for them)
Heart (when the fat Wilson sister still looked good)
Cheap Trick
Styx
Tesla (8x - wife is also a huge Tesla fan)
Motorhead (3x)
Thin Lizzy (2x - both times with Phil Lynott, including their last concert)
311
Warrant
and many others that I can't remember at the moment.
Edit: Some others that I forgot:
James Taylor
Steely Dan
Damn Yankees
Jackal
Pat Travers
.38 Special
Outlaws
Molly Hatchet
Sevendust
Chevelle (not a huge fan but, man, do they put on a great live show)
Shinedown (2x)
Collective Soul
Romantics (3x)
Men at Work
Huey Louis and the News
Disturbed