Wanting to take advantage of a great camera

I just bought my first SLR camera, a Conon Rebel Xsi and other than just fooling around with it, have no idea all that it can do? My wife is a professional model and we would really like to start taking some amazing pictures. We dont have a studio or anything, just what the camera comes with and a beautiful subject to shoot, what are some things we can do with what we got to take some really beautiful photos?