Here is a great forum to check out for the Big G.

http://www.wmi.org/bassfish/reports/alabama/

A few of the guides on there say the fishing is HOT every single day of the year in an effort to drum-up buisiness, but read through them and you'll find out the genuine guides vs. money hungry guys. I've used two guides that post regularly on that site and trust that their info is legit - Spinnerbait Kid and Fish Lake Guntersville Guide Service. Both are great sources of info.

Good luck and have fun, Guntersville is one of my favorite lakes to fish!!