I use a program called Acoustica. I downloaded it online a couple of seasons ago for around $20 and I find it really easy to use. It only uses MP3 files so you may have to convert other audio files to use in the program but other than that I have had no issues with it for mixing routine music. Good Luck!
Every editing program is roughly the same. Once you get over the initial learning phase, it is great to be able to do your own editing. Face it, most cheer teams don't require 'professional' mixing, over tracking and complex beat matching. Most of us are content to simply cut in clips of pre made cheer style music. This program is quick and painless.
Be careful with Audacity's free download. I used it to mix an entire routine(several hours of work)but when I finished and burned it, I was shocked to hear the Audacity "promo" voice over, claiming that I was using a demo of Audacity and if I wanted to learn more blah blah blah...
I couldn't get rid of it. Audacity really isn't that expensive and it is easy to use once you get the hang of it. If you have the time and patience, go for it. I do school cheer as well and completely understand the financial limitations (a lot comes from my own pocket) but honestly, it is so much easier and faster to find someone who knows what they are doing. Good luck!Cheers!