Lots of trails around Chambersburg, white tail mtn. May start doing DH there soon. Travel up to Reading for some good DH with Shuttling on weekends www.readingracing.com we got a lot of trails and we shuttle DH on ocaision alwatys willing to show you around or hook you up.www.kranzelbike.com we are about an hour north Diablo is about 3 hours away best lift access on the east coast. rattling creek single trackers I think are in lykens, cool trail networks/
If you are moving to Central Pa then you want to set up shop to the West of the city.
Like in Mechanicsburg or Carlisle......i live in Carlisle and commute about 22-23 minutes to Harrisburg to work. Around harrisburg there isnt much riding but to the south in Michaux/Whiskey Springs there is a ton......and not many riders really. The trails are not over used by any strecth of the imaginiation but there is some really good stuff. Most of it very rocky and very technical......that also keeps the number of riders down.