I just did research and bought an hdtv myself. I'm a techie by nature, if you have any questions send me a message or ask here.
There's plenty of pros and cons, it's all personal preference. If you get a good quality HDTV you really can't go wrong.
Plasma: you get a nice bright screen, with deep blacks. Your price for screen size is in the middle range. can be hung on walls or put on a stand, thin tv depth, most of the screens are glossy which can add to major glare and reflection problems in rooms with a lot of light
LCD:also a nice bright screen, however the blacks aren't as deep. Some of the cheaper lcd's suffer from a slight streaking with fast motion, but only the cheap quality ones. Prices aren't so bad until you get into the 40" range and then after that it skyrockets. They can be hung on walls or used with a stand, and have a thin tv depth.
DLP: the new generation ones have a bright screen, but make sure it's a new model with a 10000:1 contrast ratio, as opposed to the older versions which had around a 2500:1 contrast.dlp has a less thin depth and can't be hung on walls, by less thin I'm talking 15"-18". there is a lightbulb in the back that costs $150-$200 that has to be replaced after so many hours, i forget the rating, but it averages out to around 2-3 years depending on use. this is the cheapest screen size per dollar out there. with dlp there is a rare event called rainbow effect that effects some people. It happens when the eye/brain can't compute the light that is being projected fast enough and instead of blending the light is picked up seperatly. You are more prone to rbe if you've had lasik for some reason. There is no real test for it other than by viewing, it's most common with darker fast moving pictures. don't get scared away by this, it's not very common, i'm just giving pros and cons here.
My best advice is to go to a couple of stores with floor models with lots of tvs' Take a good look at a lot of them, and when a sales associate comes over ask them to change the channel to several different ones. A lot of those tv's run on demo modes or are fed a very high def feed through the store from a computer to look their best. Also don't sell yourself short and get a 720p hdtv. get a 1080p model. All HD is now broadcast in 1080i with 1080p to be in the future when the infrastructure is there to support it. It's not worth dropping a grand on a 720p tv when you could get full HD for 200 more.
other things to look for is connectivity, how easy is this tv going to make your life. Look for HDMI connections, the more the better, this is the new standard of HD, it's one connection that carries both digital audio and video, that means less cords to have behind your tv, you'll also want atleast one if not two standard coax connections. RCA type inputs are also always good to have, with all of these, more does mean better. a word on hdmi cables. Buy them online, get cheap ones. They will try to sell you high dollar cables in store. don't be scared by what they say. HDMI is all digital, meaning it's 1's and 0's, which means you either get the signal or you don't. Better cables don't give you a better picture and the signal can't be lost. The exception is if you are planning on running more than 20ft of cable, then you will need high dollar gold plated shielded cables. There is no need to pay $150 for a 3 ft section of cable that can be had for $15 on the net and perform just as well, and besides if you're cable falls apart, like they salesperson will likely say, you can buy 10 before you should have bought that high dollar one.
HD is also broadcast over the air, just like regular tv, all you need is an antenna and a hd tuner, which is built into most hd tv's, but check just to make sure. over the air HD is hit or miss with recpetion, because it's digital. Therefore you'll probably need a good directional antenna, I bought a panasonic silver sensor that I have inside next to the tv and pick up all kinds of channels for $25 at circuit city, I occasionally have to rotate the antenna towards the tower however and that just takes playing around. Atleast until you get or to supplement your stallite or cable hd tv package.
Here is the best resource I can give you, I leanred pretty much all I know about hd tv's from here
http://www.avsforum.com
And for the curious, I have a 57" mitsubishi dlp model wd-57731. It has all kinds of connectivity, I watch in a room that's filled with sun. This tv is solid, great picture, bowl games in HD is awesome, as well as pro games, and nascar. I was suprised with the ease of use, it detected all of my inputs and even knew the type of device it was. I can use it as a computer monitor with no loss in quality, it's outstanding.
like I said if you have any questions about hd tv, my tv in particular or just general questions feel free to ask. I think all forms of hd tv's have thier pros and cons, i'm not biased towards dlp because I won one. I'd love to have a 55" plasma only I couldn't justify spending a grand extra because I wasn't planning on hanging it on the wall.
I hope this helps.