Rocklahoma 2013 looks promising this year, with Guns N Roses, Alice in Chains, Korn, Cheap Trick, Steel Panther, etc.
http://rocklahoma.com/
Edit: Decided to see how good of a ticket I could get for the FM show in Tulsa on May 1st, pulled up a decent floor seat (F5 Row E Seat 1) but I wont be attending due to possible conflicts with work schedule.