Taking off the screen protector

I just got some new tubes for my nano for xmas, and as you know they don't come with a screen protector. I managed to find one that came with my old case (ironically, that one didn't even need a screen protector. Go figure) So, I put it on my nano, and guess what. I did it wrong. It has air bubbles & you can see a finger print that's on the other sticky side. So, I tried to get it off to fix it, but it's not coming off!! I don't want to start clawing at it for fear of more scratches. Is there a trick to removing screen protectors?

Also, once it's removed I probably won't be able to reuse it, so does anyone know where I can get a screen protector by itself? I tried doing a search for them, but the only types of things I've seen are the full body wraps, and that's not what I want.

Thanks!