I use Costco photo labs. They subcontract out their gallery canvas wraps that I use most often. They offer 1 hour printing in store. A glossy 8x10 or 8x12 will set you back $1.50. 20x30 canvas prints are $70 and take 10 days.
I've also used MPIX online services, highly recommended by Scott Kelby & his crew. I prefer Costco.