For your friend, it's likely Priceline can't be beat for him, but I don't recommend using their call in service. If you or another friend can give him access to the Internet and he decides to try Priceline, he'll need to bid Fri-Sun in order to insure he'll be at his destination on Saturday morning.

I'll be happy to help him bid if he posts to the message board I host, providing all of the requested info. from the Airline Ticket FAQ category.
http://pub4.ezboard.com/bpricelineandexpediabidding

Please tell him that he should pretty much write off New Haven for a cheap deal. PVD-JAX is a Southwest-compete route and will be significantly cheaper than flying anywhere out of New Haven.