Don't be chicken you'll be fine! I was able to take out and replace a stone in one of my cheap rings with a MASSIVE pair of TOTALLY wrong pliers so it should be really easy with the right tools.

Just buy a $5 ring from Clair's to practice on until you feel comfortable. Just practice lifting the prongs, taking the stone out and puting it back together again.
My boyfriend gave me the skeptical "you're going to make jewelry?" look, lol but once he sees this he is going to have to take it back!