I have a very budget oriented setup, but the quality is actually surprising. My basement is not finished, everything is on gypse, but here's what I did.
First, finished up the wall I am shooting on and painted it with Sherwin-Williams ProClassic, Extra White, Satin, Smooth Enamel Finish, # B20 W 51. Why that paint? Well check this out: http://www.projectorcentral.com/paint_perfect_screen_$100.htm?page=Paint-the-Screen. Basically this will show you how to setup a wall on which you can project, and for cheap. It basically cost me $50 of paint and rolls. They say it is actually even better than a StudioTek 100, which costs a fortune. I'm incredibly happy with the results.
Second, the projector. Again, had to be budget conscious so I got a Viewsonic PJD6531w. I needed it for business too. I got to say I am actually incredibly impressed with this little guy, cost me $650 a little while back, and the image quality is great. My father bought a level above by Viewsonic (not sure what the model would be today), but I like mine, and don't really see the difference with his.
Third, I got an older Pioneer amp and Sony speakers for my surround sound, and I had a few extra couches, so I'm using them for now. Keep in mind I'm still on concrete. The sound is truly basic, I have a much better system upstairs (Onkyo amp, Polk audio speakers), just don't feel like moving everything.
The result is incredible, especially considering I got away with spending $700 for the projector/screen. I have a total of 180" across (almost 15 feet wide). The quality of the image is great too. True, the blacks could be blacker, but I don't really notice it. However, when watching hockey, the colors are amazing, and the white is hella white!!! I feel like the game is faster when watching it on this. And the friends that come over to watch the game are always saying they have a hard time watching it on their 55" back home!! I'm always downstairs to watch TV, play movies or video games. Never get bored of it.
If you have any questions, or even if you want to see it for yourself, let me know.