You might want to call the HHI resort (843-341-4100) and ask them if they can send you one of the little golfing guides that are free all over the island. They don't necessarily describe every single course (they're basically advertising tools), but you can get a lot of information about the courses from them.
Also, ask them to send you the golf rate chart. This is something that you can request when you check in -- they don't normally just give it in your welcome packet. Even if they don't have the rates for the time you're going to HH, you will be able to get an idea of what the costs of the various courses are.
DH and DS love golfing on HH. I think their favorites are the Golden Bear at Indigo Run and the Tom Fazio course at Palmetto Dunes (which was closed for complete renovation this summer, so it may be a little different than it was before). They also like the Shipyard course. All of these are fairly close to the Disney resort.
If he'd like to play more golf (i.e., less expensive), there are several new courses further towards the mainland (Fuzzy Zoeller's Island West, Rose Hill, etc.) I'm sure they're great courses, they're just not quite as convenient.