Yes, partition magic is commercial software.
I used BootIt NG, available from www.terabyteunlimited.com
Download the program, run it to create a boot floppy, restart your computer with the disk in your drive. It will allow you to resize your existing windows partition without destroying data.
Note that there is always a chance that any partitioning program could destroy your data. Make sure you back up any important files just in case the worst happens
You should just be able to make some free space. The install program will normally allow you to create the neccessary partitions out of the free space and format them.