You'll want to get an A/V processor, not sure what your budget is however that TV costs $2500 on Amazon, so we'll figure $2500-$3500 for your audio budget, which leaves you in great shape.
An AV processor is basically the device you've described, it takes multiple audio and video inputs, drives a video signal out to the display, and audio signals out to an amplifier (it acts as a preamplifier as well).
I'd suggest Rotel, harmon/kardon, Yamaha, McIntosh, and Denon (theres a lot of price delination with those brands, and h/k might even have a reciever processor device)
Something like the Rotel RSP-1068 seems like it would suit your needs:
The RSP-1068 costs about $1700 US, so it might be a tad above what you'd wanna pay (figure you'll pay another $1000+ for an amplifier and $2500+ for speakers with that configuration), another option would be a multi-channel reciever/processor unit, which will combine a basic power amplifier and AV processor features, such as the RSX-1057, it'll provide 75w/ch for 5.1 (5 channels, subwoofer is powered on its own amp), and costs about $1300, leaving about about $1500-$2000 for a speaker setup, which is realistic
For speakers, theres quite a number of options, I'd look at Bowers & Wilkins, MartinLogan, Kef, Dynaudio, Genelec, Infinity, Klipsch, NHT, Paradigm, Wharfedale, etc (basically get away from low quality HTIAB/COTS equipment, you're after quality, no reason to avoid it)
You'll really have to decide for yourself what sound you like, if you end up choosing speakers that will need more than 75W/ch, you'll need to go with a preamp/amp solution, which will get more expensive (welcome to the world of home theatre)
Another option would be to change your TV decision and go with Bang & Olufsen, which will be a more or less all-in-one solution (they'll sell you everything, TV, speakers, remote, etc, it may not be competitive with a $50,000 HT setup, but it'll be simplistic and functional, and high quality) B&O will offer a unique look and performance level, but you'll need your whole budget to go there (which is why I say back out of the Sony to go B&O)
Check B&O out online at:
Or you'll have to find a local store (in my experience the presales customer service for B&O is a cut above most boutique hi-fi stores)
One of the nice features of B&O speakers, that presently no other manufacturer offers (at least that i've seen to such a degree, Altec Lansing has a similar technology though (I would never suggest Altec Lansing for HT)) is the sonic lens technology, which creates much less directional audio (it helps minimize the cabinet apperance, which improves the soundstage and imaging) although as I recall the speakers equipped with it cost somewhere around $3500/pair (could've changed with new models)
If B&O isn't your bag, and you end up looking at more "conventional" HT setups, I'd suggest Martin-Logan speakers (if the sound is to your liking, some people don't like the imaging on ESL's) or B&W's 600 and 700 series products, Dynaudio also produces an exceptional speaker
Im moving into a new apartment. Im planning to buy a 60 inch Sony KDS-60A2000 tv and need speakers to go with it.
I use the tv for my ps3, bluray movies, my wii and hd cable.
id like to get a set that i can plug in my hdmi cables from the ps3 and cable box with just 1 cable going to the tv and the system doing all the sound work.
I dont need loud sound but i do need quality. Id like it to be somewhat future proof and while price isnt to much an issue i could see my upper limits being around the price of the tv.
htib are ok if they get the job done but i wouldnt want one with abuilt in dvd player.