hey!I havent seen you around here for a while!Glad your back for a while!
here are some leash-free parks that i found..

http://austin.about.com/cs/pets/a/leashfreeparks.htm

and this...
http://www.ecoanimal.com/dogfun/texas.html

edit-
and this..scroll down to parks
http://www.dogfriendly.com/server/tr...TXAustin.shtml