Well guys-I hope I am in the right site.
I just purchased a two door black 4x4 tahoe with 65k for $8500.00
I am looking to put a nice system/tvs/alarm and alot of performance parts. But this is my first truck. Therefore I would appreicate any and all types of ideas. Like links and other sites and forums.
Thanx in advance guys.
Need more info. Price range. What type of system do you want? Sound quality? SPL? Looks? Do you want modifications (like remove back seat for a system, new exhaust, ect...) done to the tahoe? Let us know.
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No jeffchicott. You've got it all wrong. all wrong. Listen to the Pimp my ride master. Go with some 4" screens under the seat. yes under. Next put some z rated tires. Because you're going to put a 2.8 L honda engine in there. Turbo that thing to push 200 hp. Now go with dual 2.5" pipes and run a ingen coffee-can exhaust. Now drop some of those awsome fake chrome hubcaps from wal-mart on those "dubs" for a sweet looser look. Now while at walmart pick up one of those neon boxes with a 10" papercone subwoofer in it. Get the coolest amp you can find (even if it only pushes 50 watts). That will add some serious bass to that system. And a good 10 or so tweeters make a good high shreeling noise from the stereo.
The next thing is that suspension. Drops are a thing of the past. Go to a junk yard and get a lift kit of an old 1970 dodge truck. A good 8" will be good. We've gotta make sure those 14" will clear the tire well. Now from here it's just some good old cosmetic looks. What's nice are massive decals. Ones that have nothing to do with your vehicle or what's inside are especially cool. Rainbow window tint and a huge sunguard tint on the front window look nice.
jeffchilcott's right with that wing thing though. Get the biggest and most colorful one you can find. That will be very essential for your vehicle.
You guys think I could work on that "pimp my ride" show? I like my ideas! 
For performance i would start with a Throttle body spacer, Intake, Full 3" exhaust (cat-back if required by law
, Definately replace ALL your wires coming directly from your battery with 0-gauge, this would just be a start.... You could super charge it with a kit from Vortech (they run about $4K)
Those other two are right though, a budget would definately help.......
Hedman headers and others are 50 state legal, I'd highly recomend them.