The High Road
The Firing Line
Real Guns
Gun Blast (depends on what I'm lookin' at; some yes, some no)
Chuck Hawks free section (I'm cheap, byte me)
And a slew of others I can't remember at the moment. They always pop up on the first three pages of a Google search. At least they do when your Google-Fu is strong.
As for what I specifically look for, its not hard to tell. If someone is giving a lot of "read this" or "heard that" responses, he gets chucked in the "Horse Hockey" bin. One or two line responses mostly get ignored unless those two lines are gospel (like fixing the rattle of a Benelli Nova fore-end; flip it over and use an Allen wrench). People who have shot a given firearm, in the field or at targets, and who have seen the effects on those targets... well, those are the guys I pay attention to. I keep an "ear to the pavement" to get a general vibe on people's take at all times, too. Look for consistencies. People rarely say anything bad about Hornady's Lock n' Load bushing system or presses, they rarely talk down about a BPS shotgun aside from weight. When it comes to some things, the line on that signal-to-noise meter doesn't move all that much. Which is precisely what you look out for.
For example, last night a Tikka T3 Lite Stainless in 6.5x55mm was added to the list in place of a CZ 550, same caliber. Why? Simple: in months of reading posts, researching, and listening all over the 'net, not one single person had anything negative to say about the T3 Lite that directly affected its operation. Sure the mags are plastic, yeah they're friggin' expensive to replace, so what if the bolt is two-piece. There were zero gripes about accuracy, trigger function/feel, folks couldn't say enough about just how slick the bolt throw was, and it costs a LOT less than a CZ. The caliber I wanted is readily available, notoriously accurate, and even in a light rifle (7.3 lbs scoped!) it won't kick you senseless or blow your ears out. Barrel life is nice, too. My only concern is that there is a single-point factory maintenance system in place... in Finland. I'd rather take it to the local guy and have him jigger with it. I found out all this just by paying attention to what people were posting.
Watch for what I call the Rule of 50%. Half the posts you'll read on Lee reloading equipment or Ruger 10/22 rifles will be Gospel According to XXXX. The other half will be Damnation According to XXXXX. Invest in stuff like this at your own peril.
If someone knocks a single-shot because they don't like single-shots, ignore 'em. If they talk down about a given item because it didn't do something it was never engineered to do, ignore 'em. You'd be surprised at the sheer number of idiots who give something a bad review because it didn't let them climb Everest in ten seconds. On the same token, beware the idiot who can't give a bad review. I'm dropping a magazine sub because one writer simply refuses to say that fecal matter does, in fact, stink.
Oh, and pay attention to the sticky threads at the top of any forum you visit. You'll get 40% of your questions answered before you burn a thread asking 'em. The rest? Search.
A Lot.