Its a buyer's market to be sure. Timbermart south has very good information, however its not specific to every area and market; they'll take state averages of what pulpwood, CNS, sawtimber are going for. If he thinks he can take bids and have folks begging for his timber, I want to see that tract. Is it road frontage? How far from the mil? Also will he do a pay-as-cut or lump some contract?
Pine plantations are generally first thinned at age 15. Sometimes as early as 12, but if you wait til 18, you've incurred some loss due to growth limitation. Second thinning about age 25, Final cut (clearcut) around 30, as late as 40. Pulpwood market is terrible right now, btw. Timber markets are regional, and the closed to the mill, and easier access for the logger, the better your chances of 1. Getting someone to even bid on it, and 2. Getting a decent price.
I'd have a trusted forester look and tell me whats out there before i bought. Beware the timber pimps. They have ways of stealing from a landowner that you've never even imagined.