I just ordered an upgrade kit for my Tahoe from SSBC. I wanted the 8 piston kit from Brembo, but the fitment template didn't fit because of the way my spokes on my wheels curve in towards the back of the lip. So the only good brakes I could find that would work are from SSBC with upgraded slotted rotors from 12" to 14", 3 piston calipers, and steel braided lines. They make front and rear kits that will fit your 99.
My kit was about $1500 for the front, but I think the earlier year models are a little cheaper. The rear kit is the same price. If you don't want to spend big dollars, then SSBC are the way to go for performance/dollar ratio. And despite the cheaper prices, they are still great brake kits. Don't remember the numbers , but Super Chevy mag had an article a couple years back with this same kit on a truck, and the stopping difference measured in feet was awesome. In my camaro/trans am club, I've rode in two different cars with SSBC brake kits, and one with Baer. The SSBC seemed to stop just as well as the car with the Baer kit.
Check out this site:
SSBC truck brake kits