I have a bunch of .wrk files from when I owned a couple of Cakewalk programs. I don't have any of my Cakewalk software anymore, though. Is there any way I can open the files up or convert them to MIDI without buying new software?
.wrk files are full project files with a lot more information in them than just the MIDI. In order to extract the MIDI information you would first have to open the files. Unfortunately this means you'd need either a version Cakewalk or Sonar.
The (perhaps) better news is that there's a trial version of Sonar. You should hopefully be able to open your files from there.