The microsoft offer is still current http://www.microsoftstore.com/store/...&WT.medium=cpc and that where I got mine from - Got 64 bit 8 pro at £24.99. If your PC is new you may be entitled to the upgrade for just £14.99 but you need to talk to your seller.

If the PC has been used for a while it may be worth doing a factory restore to win 7 to clean off all your old stuff and then do the online upgrade. Needs an operating system to upgrade as I believe that you cannot clean install.

Cheers, John