I prefer to mirror the TexLive image using rsync and build from that, if I have enough disk space on the machine I want to build on. tug.org recommends other options at the TeX Live availability page, which has links to building TexLive from DVD, the iso, and live internet install, the last being the most bandwidth and disk space efficient, since you don't download material you don't ask for.
You might consider complaining to CentOS' Tetex package maintainer: they are one of a number of *nix distributions that offer Tetex and not Texlive. It's a nuisance if you want to use the package manager to install things to depend on your Texlive distribution when the package manager only knows about Tetex: you might be best off not deleting the package in your system but rm -rf the installed hierarchy containing the texmf directory, and making it a symlink to the Texlive installation. I've had this trouble with Fink on Mac Osx, and I just install everything that would depend on Tetex by hand: you'd be surprised at how much there is.
I recommend installing Texlive 2009: Texlive 2010 exists as a pretest version