Don't be afraid that you will need to transpose everything! Music written for band will always be already written in the key you need. It is only when you're trying to play with others and they do not have music written for each part that you will need to transpose. There are several music-writing programs for the computer that can transpose parts automatically, for those who cannot (yet) transpose by sight, if you have the time to enter it in, and then change the key. When I get music ready for small bands at church, I use the program called "Scorewriter." It is much more affordable than the high-end products like "Finale," and does everything I need it to do.