This article at Hazelware talks about how you can figure out the name of the WiFi access point to which you're connected. It's a bit of an ordeal, and he had to dig through lots of poorly documented headers and do a lot of tests. Fortunately, he's shared that info so you don't have to figure it out yourself.
The Hazelware site has a lot of other good articles and a useful programmer's utility program, Palmasaurus.