I used this version of Protracker back in the day on my Amiga 500. I use this one now as it seems more emulator and HD friendly. Might even work on a500. If you want to go further back in time NoiseTracker and any of the old Soundtrackers will work too, though they have far less functionality than PT.
If you want to try something other than chipmodules there are a lot of specific editors from the old days. afaik AHX doesn't run on a500 machines but, for example, Future Composer does, though I don't think it comes with docs.
There's a whole bunch of other 'chip' ones in this amigascne folder. like BugMon, JamCracker, Sidmon. Probably some others, I forget the names. Some of those are a1200 only, like Art Of Noise.
Oktalyzer and StarTrekker are 8-channel trackers (software mixing), but they were both quite early so are missing a lot of functions that Protracker has.