Watch the The Saints online guitar lesson by Mimi Fox from Flying Solo
It's very important to listen to as many versions of a piece as you can find, BEFORE you make your own arrangements. This way you are storing all the musical data in your brain on a subconcious level. You can also begin to feel out where you want to go with a song by how these different versions make you feel. Stay open, and don't pre-judge. I have heard really cool arrangements of tunes that were done by rock groups that I didn't even think I liked! The best musicians are the ones that never close their ears, their hearts, or their minds.