On the Knoppix disk there is a usefull gui program called qtparted. With this you can resize and add partitions. Also cfdisk is very good. It can't resize but it is easy to use. Once you make space for a swap partition you do not have to format it. But you do have to mark it with a swap flag. I don't know how this is in qtparted but in cfdisk you just change the partition type to swap. When you run qtparted of cfdisk you will know if you have a swap partition or not on the main screen.