I-76 PA to I81 to VA/TN to I40 to Memphis..ideas, please

There is a KOA at Staunton-Walnut Hills VA. Tent site no hookup $20 base rate.
There is also a KOA at Natural Bridge VA and one at Wytheville VA.
Another possible stop is the KOA at Crossville TN. The good thing about KOA is that they have bathrooms, some supplies in their stores and usually have camp hosts or managers on site.
another option would be a truck stop. There are several Pilot Flying J truck stops along that route : http://www.pilotflyingj.com/locations
have a safe trip!