It's been a long time since you posted this, but I'm going to reply anways.
I'm not certain about the hosting, but I imaging you'd just need a host who is willing to let you upload flash files, as it is really up to the viewers/surfers to have flash installed on their computer.
I've never done anything like it, but you may need PHP includes or something to make the flash file actually appear on the page... I don't know.
If you're looking for a host to experiment with though, I'd be happy to give you some space on my domain, www.simple-dreams.net . I'm really curious about it now, as flash sites are something I may explore in the future.