I guess it depends on what part of stormtroopers you are looking for. FISD is the place to go for 501st stormtroopers, however as we're very 501st-centric and have to abide by 501st rules, there is some territory we don't cover.
For instance the RPF (Replica Prop Forums) focuses specifically on prop re-creation, so if you're in to that part of the hobby that's a good resource though they discuss many other types of props.
There is another fantastic site that escapes me - TKsomethingsomethingsomething.com that focuses very much on building vac tables, making molds, etc. and those parts of armor making, but for instance don't talk about trooping or the 501st really at all.
There are countless sites out there such as Tony Barnett's, Dean Plantamura's etc. but these are mostly static content sites with tutorials but no forums.
I guess it would depend on what type of info you are interested in.