There are plenty of programs that remove iTunes’ DRM, but it’s hard finding one that is free. That particular one appears to be commercial; like most such programs, you’ll be shelling out $30–50 for it.

It is worth noting that the MPAA and RIAA like to sue people for millions of dollars, so there is a bit of a “chilling effect” on free DRM circumvention. Combine that with those who use DRM altering their methods as soon as they are cracked, that makes it a little tricky to find something workable and free.