It's unlikely there's any such site, so you'll have to do this in stages. Go to a couple local stores (with Circuit City going out of business it kind of reduces your options) like Best Buy, Fry's if there's one in your area, and even places like Walmart, Target, Sears/K-Mart. Write down the EXACT model name of any set that looks interesting to you, and then take that list home and start typing them into Google (or your preferred search engine) with something like "reviews" at the end. You can check Amazon, NewEgg, and even Cnet to see if they either sell that same set or have a review up. You should be able to get a detailed list of the specs from sites like NewEgg or Amazon, and also some user reviews. Odds are the reviews will help you knock at least a couple sets off your list because they'll be universally bad.
The resolution part don't worry about, because HDTVs only have 3 resolutions: 640x480 (480p), 1280x720 (720p), and 1920x1080 (1080p). Doesn't matter how big the screen size is, maximum resolution is going to be 1920x1080. The only thing that changes is either the size of the individual pixels or the space between them.
As for the rest... All other things equal, wider viewing angles, lower response rates, and higher contrast ratios are what you want to go for. The higher or lower the better, depending on the metric. Honestly, I have a pretty standard 32" 1080p set and it works just fine for all my gaming needs. I don't play a lot of FPS type games, what I play is probably a lot closer to WoW than a FPS, so I would imagine virtually any TV will be fine. But obviously if it comes down to 2-3 sets, and it's a tossup on the major factors like price and display quality, lower response rates, wider viewing angles, and higher contrast ratios should help pick a winner.
On to the audio side of things...
Any HDMI capable receiver will have what's known as HDMI passthrough abilities. So you'd take the HDMI cable from your PS3, plug it into the receiver, and it would then strip out just the audio portion sending the video on to the TV through another HDMI cable. Some higher end receivers can even do signal conversion, so you could take an HDMI input and have the output be component video or even composite. Or the other way around, so let's say you decided to get a Wii some day, which only has component video, you could take that component video, and have the receiver send the output signal over HDMI. A lot of this stuff will be a lot easier to figure out when you have the actual receiver in front of you, assuming you can think in a fairly logical way.
As for wireless speakers, I've never used them, so it would really probably depend on what kind of wireless tech they're using. If it's some kind of Ir based setup, run for the hills. You have a friend over, and they need to use the bathroom or something, it might cause one speaker to cut out momentarily as they broke the line of sight. If it's some kind of RF signal, then you'd have to be aware of things like cordless phones, wireless routers, etc. Those could potentially cause interference depending on their respective frequencies. So, while you should probably take this with a grain of salt, since I've never personally used them, I'd say that they should be lumped in with most wireless networking. Better in theory than practice. Do like with the TVs, and check some of the reviews for them on sites like NewEgg and Amazon. If some set has hundreds, even thousands, of largely positive reviews, then you can probably assume they'll work well.
And subs also do what is called LFE (Low Frequency Effects) which really more than anything helps create the sound field that creates the surround sound illusion. Think of it like a person who can throw their voice. The more precise the sub is, the better it can make it really sound like there's some explosion happening right behind you. The better it can compliment the sounds coming from any individual speaker, the more realistic the sound. And obviously a sub is only one speaker, so can only generate one frequency tone at any given moment, which is why 3-way speakers can make a difference. Each speaker having something of a dedicated sub can help make up for some of the limitations of the main sub. They're not a replacement, but more an augmentation.
Again, this is an all other things being equal. Get the sub and speakers with the greatest frequency range that you can afford, and do a little cost-benefit analysis of your own. It's probably not worth paying 1.5-2X more for a speaker and sub set that has an extra 4-5Hz range for example. If it's only an extra $50, and you can afford the $50, then maybe.
Like any major purchase, the research phase takes a long time if you want to do it right. You need to become something of an expert in your own right. Lucky for you, you have at least 2-3 months to wrap your head around all of this and you can even get started on the TV end of things now. Hit some local stores, see what there is to see, and start looking for reviews.
And I will say that one thing I like about Onkyo is their Club Onkyo site where they sell refurb units. They're labeled as refurb, and so they say may contain missing cables or have minor cosmetic damage, but I think 90% of the stuff is just models they've discontinued and are looking to clear out of their warehouses, so they sell them at a discount. I've bought two off of them, both looked like they could have come right from a retail store. One had a bum IR sensor, but Onkyo's CS dept got me set up with a replacement pretty quickly and painlessly. But don't buy an Onkyo just because that's what I've used. Look around, read reviews, make a decision based on what you think sounds good.