Hello and welcome
It sounds like we're both at the same stage in planning. We're having ours, late May 2011, and heading over there in July to meet the venue etc.
As for entertainment, after a bit of research I have just decided to just hire a sound system, and I'll bring my own playlist on iPod, MP3 and CDs, just in case something isn't compatible. I have 13 months to put a playlist together, when I hear songs we love I'll just add them as I go. The sound system will be sourced by my venue's function manager, I didn't have much luck finding one myself. Agreed on US$200 (started off as 500!) not sure what to expect, but we're only having around 20 people.
For the photographer, not familiar with Iwan but if you haven't already, google him and check out his galleries. And make sure you haggle, I got a bonus hour for free but I really could have tried harder to get a discount for booking early.
Not sure I'm much help
but also interested to hear what others have to suggest about entertainment.
Good luck with it all