Target has Guitar Hero 5 with Guitar bundle for PS3 on clearance for $11.24.
This is most certainly YMMV. I do not know if they are also selling the
360 version, but might be worth checking into.
Check your local Target's Inventory: http://sites.target.com/site/en/spot/mobile_fiats.jsp?title=fiats&dpci=207-24-0273&desc=Guitar Hero 5 Bundle for PS3 $11.24 in Target Stores YMMV