Apparently there was no native GNU/Linux build of Musicmatch. What was done was by running Musicmatch via Codeweavers WINE port.
Running MS Windows applications via WINE is done with many programs.
Not really sure the GNU/Linux world needs a closed source project like Musicmatch. As Musicmatch was a shareware project. Cost was $19.99.
There are ample music players that are OSS/FreeSoftware for the *nix community.
Madman
Rhythmbox
As far as Oldversion.com hosting older version's of MS Windows, GNU/Linux, *BSD, QNX, SkyOS, OSX, Solaris, OS/2 software... There are far to many Operating Systems to host every single older software title of.
But to narrow the topic down to just GNU/Linux builds. The decision would be to host which. RPM's, tarballs, tgz, pkg's, source? Then which distro should be chosen, as there are hundreds of GNU/Linux distros...
OpenSource and Free Software are great models. But without some way to make money programmers are not going to keep chugging out great code without some form of reward.
Xanadros is not entirely an OpenSource role model, (where is the source code?) As they take code from the Debian GNU/Linux project, which is Free Software/ OSS. But you do have to pay for Xanadros. I believe some of the magic of Xanadros is that it relies on ClosedSource drivers and commerical software. Such as Codeweavers.