Generally there's no need to actually install an VC runtimes seperately as they come bundled with programs that require them and those programs' installers will include them and install them for you. There are components (such as the runtime files) that are installed as part of the OS, but they won't show up in Programs and Features
because they can't be removed.
The latest redistributable for VC 2005 can be found here
and the latest for VC 2008 can be found here
As I said though, if you do need them an application will install them on its own.
Edited by exile360, 01 August 2009 - 04:41 AM.