Man, thank you all SO MUCH for the information! I got a second opinion on the brakes from Goodyear since I already had an appointment with them to install a new set of tires. They said that I do need to replace both rear calipers, that the left is completely locked up and that the other one is not much better. Funny because the other place said the right side was worse. Both places said that my vehicle has a "special" caliper and it has to be ordered from the OEM because nothing else will fit it. They also quoted me around $1500. I don't mind paying extra for decent parts, and I don't know really anything about working on cars, but that seems outrageous. I do know that most of the cost is from the calipers, which run around $400 from the OEM (and after shops up-charging the **** out of it).
But I think I have a plan after talking with my buddy. He actually suggested that it's probably just the pins like someone else in the thread suggested. I'm going to get new caliper pins, pads, and rotors locally and have him replace everything for me. His wife has a CR-Z too so he's used to working on her car and has all the tools already. If I actually need new calipers he will let me know.