A bird's eye view - does not cover creating disk partitions.
Recommended tools to view your current partitions:
gparted - launches a GUI
parted - begin this command line program, and type 'print'
The partition addresses you're looking for will most likely be in the format:
First allocate the space for the partitions, and then resize the partitions.
gparted has a "Move/Resize" option, but this is not in fact resizing, it is just allocating.
Important: Assuming you want to keep existing data, you should resize the parameters in such a way that existing allocations do not move. I believe this is otherwise known as leaving the original "cylinders" in place.
1) re-allocating your partitions:
fdisk fancier command line tool
quick check to see that all is ok:
2) resizing your partitions
Lastly, you should be able to run:
[sudo] resize2fs [/dev/sda[X]]
And it should automatically resize the underlying drives to your allocations.
So what is the difference between resizing and reallocating you ask?
That is a very good question! And one that I have yet to find an answer to.