Between Blacksburg and Roanoke:
https://smartwaybus.com/smartway.html
From Blacksburg to NJ and others:
https://www.collegetransit.com/VT-s/108.htm
Amtrak and Greyhound also look to have service. Suggest searching on Facebook for rideshares. Tech (and JMU) are very popular destinations for NJ students, so you should have pretty good odds of finding a ride.
There’s another bus service I believe that takes you to NoVA. One cautionary note - the bus ride is close to 2.5x as long as driving by car due to all the stops between VT and Fair Oaks Mall in NoVa.