Washington DC
OK...seriously....
The vast majority of providers are availble evenings/nights. I happen to like the early morning get the day started right kind of interlude. Any good providers out there that serve breakfast?
The best way to insure they happen is if they are set up at least in advance. At least by one day. 
Related Link: website
A regular-of-mine and I often did 7 or 8 am sessions. She kept telling me that she was up for earlier sessions, so we tried a 6 am and decided that we weren't quite up to that!
The best morning sessions are overnights, where you can start some action at 0-dark-thirty, get it done, and go snooze til morning again... 