If you aren't from texas and haven't see the Austin Capitol city tour (Take the Duck Tours for some fun and great Texas Capitol sites--very historic), Try to get a tour of the capitol building. Look up in the rotunda. It is very beautiful and unforgetable. I don't know when the bats will be coming out or if they are there at the Congress Ave. bridge. Ask at the Duck Tours place downtown and they should know. It's fun and they have pontoon boat river tours which is nice to slow down and see nature up close.
There is also the LBJ ranch and tour, The Ladybird Johnson Wildflower Park--you can buy plants too.
Texas is full of historic places and lots of folks to tell you all about it. Just stop at a town, find the Dairy Queen and ask the oldest person in there about their history and you are off!
Del Rio is a wonderful town and historic as well. There's Luckenback, made famous by the song and where there's a chili cookoff each year sometime.
On your way out of Texas, check out Marfa with the mysterious lights
at night that's unexplainable! It has many artists living there so you might find something nice for the house, or rolling stock.
If you go up toward Lubbock or Amirillo, there's the Helium Museum where they discovered helium! pretty cool.
Hope this helps.