hehe people seem to forget that all the celeb's don't setup their own phones =p
if you're on cingular, go to
http://www.cingular.com/blackberrystart
once there you can enter your hotmail account information and it should start pushing to it immediately (i assume its like gmail).
for AOL, you can get the free Ramble IM, or if you want a little better program with support and all the messenger services, go for IM+