Flymia, there's a lot of good information in this thread, if you can sort the wheat from the chaff
If you want some USAF-specific information, pay good attention to what rivetjoint has said. Also, you can PM or e-mail me. I've spent many years as a USAF pilot, much of it at the initial-training bases as an instructor.
One good thing that both the RAF and USAF folks have said, that you
must take into account, is this: Do you really want to be a
military aviator, with all that entails? If so, then great -- you should go for it. But if you're just looking at the military as a way to get your flying hours, you may end up very unhappy.