Hiya,
The chrome download page at
http://www.google.com/chrome/ should spot that you're using CentOS and - possibly after selecting a language - the download button should provide you with an rpm file you can click on to install. (Never tried this, just a well educated guess!).
You should, however, check your software repository to see if it's there. If it is, you'll get automatic updates, no dependency problems, and all that good gear. Click and browse, basically!
CentOS is Fedora/RH-based, so if you can't find an application - any application - you want in your add/remove software app, search for it on the net, and when you get to the linux download area you'll usually see a choice between a .deb and a .rpm file. You want the RPM version.
Hope this helps...
