The Copy Shop in downtown Bloomington is great. They did all my wedding invites much cheaper than any other place, so I would think they would be able to help you out.
Shutterfly has sales all the time so maybe something from them. Peoria Camera in the Metro center in Peoria does large prints too but I don't know how much they cost and what you consider cheap.
Thanks! I appreciate the help!
Click on each tool to see a sample.