Can you use a regular Straight Talk SIM card in an unlocked AT&T iPhone 4?

So I have an unlocked iphone 4 that has GSM and all that jazz that you need to be able to utilize striahgt talks phone services. My problem is is that I knew I needed a Straight Talk sim card to put in the iphone. I went online on Straight Talks website and selected the simcard they had available. Little did I know that apparently I need a micro sim and the one they gave me is a regular sim I'm guessing since it's too big to fit. My question is, can I cut the sim card and use it?

Yes, you can but the SIM and use it. Check online for video tutorials.