If all you're looking for is a simple graphical-frontend for Snort, you can go with something like
ACID . If you want something for graphically administering Snort itself, there is a
webmin module available. Personally I think manually editting the snort.conf file is the best way to learn about all of its functions and using a point-and-drool interface really limits how much you can learn about some of the more powerful tools like Snort, my 2-cents anyway.