it was a blast!
it was easy for me to set up, because i contacted a surgeon who had previously worked on me, and we had a good rapport. i would just call his secretary the week before, say when i could show up, and she'd tell me where to be; piece of cake. i followed him around for both office hours and lots of surgeries (by far the most interesting--though the office visits provided lots of learning opportunities, too). i thought it was frickin' great, but, like i said, i shadowed someone i already knew. i think that made it easier on me as far as adapting to the environment and feeling comfortable.
if you don't know anyone, ask your family doc if he/she has any recommendations. failing that, if you live close to a med school, look up the orthopedic surgeons listed as faculty on their websites and start sending out some emails. what's the worst that could happen?