How can I remove a phone case/cover from my phone?

I have a sprint LG rumor 2. I bought this phone case off of ebay. http://cgi.ebay.com/PINK-RUBBER-HARD-Case-Cover-SPRINT-LG-RUMOR-II-2-/190431295042?pt=PDA_Accessories The back broke so it's off but now I can't get the faceplate off. How can I do that without breaking my phone?