So did your OEM vista didn’t come with Vista install media? Never fear, you can obtain media for free from these sources.
Some claim that if you use your OEM license (say sticker off the bottom of your laptop with Vista Ult 32bit) to do an install, it might not accept, but its worth trying. The main benefit will be to do a repair install, something you can’t do when you only have OEM image CD’s.
There are whispers that if you have Vista Ultimate 32bit license, you can install 64bit version with the same key but on retail media, not if you have OEM license.
References:
http://www.mydigitallife.info/2007/05/08/windows-vista-free-direct-download-link/
http://www.mydigitallife.info/2007/12/22/64-bit-x64-windows-vista-official-direct-download-links/
http://www.mydigitallife.info/2007/05/10/how-to-make-vista-bootable-dvd-with-wim-downloaded-files/