Is that 11.1 GB the size of the whole hard drive? Or do you have unpartitioned space or do you have other partitions you didn't mention?
Do you have a more significant reason to want to increase your swap space or are you just following some formula that says it should be double the ram size?
You can use the partitioning tool when booted from a liveCD to move, shrink and grow partitions as you like, and you could increase that swap partition without losing data. If you move the boot partition, you might need to reinstall stage 1 of grub, but that is also easy while booted in that liveCD.
Before trying any of that, you should have a better idea of whether increasing your swap partition size is a good idea. From the little info you've provided, I would guess it is not.