WINDOWS COMMAND LINE SOFTWARE

The simple disk_part in command prompt (cmd) does the trick. This comes with every Windows.

Here are some good articles on how to use it:

http://www.jwgoerlich.us/blogengine/post/2009/11/05/Use-Diskpart-to-Create-and-Format-Partitions.aspx

http://helpdeskgeek.com/windows-xp-tips/diskpart-windows-xp-help-use/

http://technet.microsoft.com/en-us/library/cc766465(v=ws.10).aspx

GUI SOFTWARE

However this free software (dont mind the adware, just make sure to not install it):

EaseUS Partition Master Free Edition

This software does everything and so easily too.