Crap.
Just ordered one of the Dealxtreme ones linked in the first post which I am now pretty certain will not work - that's gotta be a mini B connector. Was ordering a bunch of other stuff (USB serial adaptor, USB network adaptor, and USB hub) for my forthcoming Pandora so the xtra $1.50 won't break the bank.
If anyone sees sellers with good prices on mini A male to B female USB adaptors please add links here or to the wiki.