Gilbert,
A real nice summary of the 5th Texas Cavalry's history can be found at this excellent website. Try this: www.bauer.uh.edu/~parks/tex/texreb1k.html
I believe that will get you to the Texas Cavalry page and you can scroll down until you get to the 5th Texas Cavalry ( not to be confused with the 5th Texas Cavalry , Partisan Rangers ) Hope this helps . Also, you can use Dr Ken Jones website at Tarleton State ( Texas) University, where he is head librarian . Try www.tarleton.edu/~kjones/
Try these sites for some good summaries of the various Texas units .