I already Have a battle.net Account And want to know How do you create a account on World of Warcraft account I Have all the patches downloaded and using a Windows7 Laptop with all the requirements

If someone already has a battle.net account, downloaded all the patches and everything, then they should just be able to log into their battle.net account management page and purchase the license keys for world of warcraft and subsequent expansion packs (currently 2 expansions).