Buy here: https://www.microsoftstore.com/store?Action=DisplayPage&Locale=en_US&SiteID=msusa&id=ThreePgCheckoutShoppingCartPage


MS OFFice 2010
http://office.microsoft.com/en-us/buy/using-your-office-2010-product-key-card-FX101853163.aspx

Produkey
http://download.cnet.com/ProduKey/3000-2094_4-10457063.html

2013
http://office.microsoft.com/en-in/products/download-backup-restore-microsoft-office-products-FX103427465.aspx


https://setup.office.com/