You're going to get a solid product from most of the big companies should you spend around $100. If you're fishing saltwater, don't buy an aluminum body reel; go graphite. (Something like the Shimano 4000D).
If you're freshwater fishing only, then I think aluminum is the way to go. The biggest aspect is looking at the bearings, and the material that they're made of. Buy what you can afford.
Lastly, test the drag system if you can. I know a lot of places don't have line on their reels, but bringing a little with you in your pocket can really help make sure you're not buying junk. Load a little line on the reel, and test the drag...it should be smooth as butter; no jumping or hesitation. (You only need to put a few feet on as you're just testing the drag)
I have had Shimano, Pflueger, Daiwa, and Penn....and will be buying a new spinning reel soon. I must admit that Quantum's feel nice, but Shimano has never let me down.