That link is a very good starting point. I recently bought my very first AR-15, so I'm no expert but have been where you are recently. Paid too much because of the "Obama rush" but I'm still satisfied with the gun. Don't fool yourself into thinking "I just want a stock gun; I'm not going to customize it" ... AR-15s are one of the most readily self-customizable guns ever made - it's like a Lego set for guys AR-15 accessories. It's not a question of IF you will customize your AR-15, only of how much.
Because of this, many will tell you to buy all the parts you think you'll want and assemble an AR yourself. Unless you're really good with assembling things, I'd recommend buying a pre-assembled ready-to-go AR. This way you can get an idea of how the stock parts all work and then decide what parts you want to change. For me, I have no desire for any of the "tacti-cool" 4-rail picatinny forearms, and the standard 6-point collapsible stock works for me. But I've found I do want a better trigger, probably an EOTech site, and have already added a tactical light, an Ergo grip, a Harris bipod and some small picatinny attachment points around the front site base.
The one important suggestion would be to get a flat-top upper or removable carry handle (A3 configuration). This will allow you to more easily add optics.
Also, try to determine before you buy what size/type of barrel you want. Standard 16-inch M4-type? 20-inch M16 type? a match-grade varmint-type barrel? heavy or light barrel in any size? If you're strictly target shooting (especially at longer ranges) and hunting with the gun, then go for a 20-plus inch barrel and possibly a match-grade. For any type of home defense use, a lightweight 16-inch works better and still gives good accuracy - 1 MOA at 100 yards is possible if you're a good shot.
As far as brands, I continually hear good things about Bushmaster (which I bought), Rock River, Armalite, CMMG, S&W M&P series, Sig, and of course Colt (if you want to spend premium money). DPMS seems to have a hit-n-miss reputation - some love 'em, some not so much. Olympic, High Standard and some others seem to have lesser reputations (though I have no personal experience with anything other than my Bushie and a friend's Colt).