If he wants to get into gas then I think I saw a add in the for sale forums that I think will suite him well.
This one:http://www.rcuniverse.com/market/item.cfm?itemId=127799 , is 150 bux and is pretty much RTF plane. he will need to make a trip to teh hobby store after consulting his club instructor.
It includes 1 tower hobbies trainer
1 full radio system
1 os 40 engine
1 hangar 9 starter
1 great planes glow plug liter
1 hangar 9 fuel pump

these are all good brands and appear in the pics still in there original wrapings. the seller has good rateings and is willing to box all this up and ship it.
I would be buying all this if I didn't allready have it, LOL.
He is still gona need a props (2 just in case you need a new one at the field), glow plugs (plural, 2 or more), a lawn mower battery (small 12v for the starter) , teh all important fuel, and a flight tote box to pull it all together.
fuel=15 bux
tote box=15-20 bux for kit, 40-50 for RTU ( go with the kit, it no take long to build)
props (10x5's probably)=6 buxs apeice x2
glow plugs=2 buxs per plug x2
battery= [&:] uhhh im not shure but it will probably be around 10-40 bux depending on brand and size. just remember, you have to cart all this out to the field so choose wisely.

What ya all think? it should get him alot of what he needs at a good price i think its inside of his price range.

P.S. I just noticed he will need fuel tubeing, a couple feet should suffice.