Ubuntu -- Partition Manager
Partition Manager has been part of the distros I have used.
Try System - Administration. Should be on the drop down list.
I am not a Linux geek - and I would not dream of advising other non-geeks to try partitioning themselves (it is not that difficult BUT you do need to KNOW what you are doing!!!). [If you do try it remember you will need a separate Linux Swap partition. Would recommend splitting rest of drive into at least 2 partitions - one for Linux, another one/two/three for data, backups,etc. Should be plenty of info on the internet and Linux/Ubuntu forums.]
However, just running Partition Manager will show you how the new disk is currently partitioned.
Suggest you also might do some searching / Googling - 11.04 is a very new distro, so there may be some nasty teething problem.