You might check out a more local fishing site.
http://www.austinbassfishing.com/forum/
Also, check out the Texas Parks and Wildlife site.
http://www.tpwd.state.tx.us/fishboat/fish/recreational/lakes/canyon/
To be honest, I haven't been to that lake since the mid-70s so can't offer much about the fishing.
Enjoy your visit to our great state. 8-)