I'll try again with the San Marcos River deal. I think it was even in some ghost book on Texas ghosts.
But supposedly there is a critter or ghost running around there near Ottine.
I also heard about some ghost dating back to the Civil War era. This happend near I think the Staples-fentress area. wwww.texasescapes.com i think mentions there was some sort of confederate camp at Staples. They also have a section on ghosts, so I'll check that.
Supposedly, there was a werewolf in Converse,Texas, who attacked a boy back in the 1800s or early 1900s, but it too is another hard one to find.