I do installs on the side and have used a couple different setups.
Luckily the 2wd Tahoe/Suburban is has the exact same suspension as the 4wd. This means that any 4wd kit will work on a 2wd truck. As far as suspension kits, you have several options. These are a few brands that have kits available: Rough Country, Zone Offroad, BDS, Rancho, Fabtech, Tuff Country, Superlift, CST, RCD, and I'm sure there are others.
Rough Country and Zone are going to be the best kits for the money though.
RC - $1300 vs $1800 for a Fabtech or other brand kit.
http://www.roughcountry.com/chevy_4wd_00-06_tahoe-6.html