I live in Virginia and it is beautiful in the fall. Monticello, Thomas Jefferson's home, is gorgeous when the leaves turn and if you can get tickets to the local college football that is also a lot of fun.
Busch Gardens in Williamsburg puts on its "HallowScream" from mid-September to Halloween with all kinds of harvest and Halloween decorations.
Colonial Williamsburg is beautiful any time of year, but more so in the fall and winter.
Washington DC is a short drive away and most of the buildings listed as "federal" or "national" are free of charge like the Smithsonian, Washington Monument, Lincoln memorial et al.
The Shenandoah Valley has caves and is great for nature buffs.
More can be found here
Virginia Is For Lovers: Vacation in Virginia
That's my plug for my state!