Office Professional Plus 2013 just made it to RTM and it is also available for anyone to download from the Microsoft’s TechNet Evaluation Center. This final version of Office 2013 includes Word, Excel, PowerPoint, OneNote, Outlook, Publisher, Lync and Access.
The download comes with a 60-day trial, but a free registration is required to obtain a product key. The bits have been released as you would expect in 32-bit (x86) and 64-bit (x64) versions and in various languages including English, Spanish, German, Japanese and others.
System requirements: If the your system is about 3 years old it is going to work — that simple–, for more specification visit the Office resources page.