Take your wheel/tire to a tire shop, have them perform a balance on the wheel and request a wheel run-out check as well. If they are using a Hunter Road Force balancer or Hunter product, ensure you visually see them run two little arms against where the wheel is and watch it spin. That will determine if the wheel is bent.
2009 Cobalt LS XFE U74
Mods: K&N Typhoon Intake, Option Cat-Back Exhaust, Cosmo Short shifter, Maxxim Ahead 17X7's, MPx shorty antenna, FE5 Strut/shocks, Tein S Techs, Moog endlinks, Moog spring seaters, ZZP shorty header, LSJ downpipe, LNF front grille