well, i didn't like much of the default notification sounds.So i wanted the ones i had on my pro.So through searching i found that there's two way of doing it.either put the file in (sdcard/media/audio/notifications) or what most people suggest but i couldn't see any files there (root/media/audio/notifications) but anyways try the first one.
Or you can download the app (ringdroid) that is attached or go to market and download from there.Its a neat program like the mp3 cutter app.Now when you use rindroid make sure if you want to save it as notifications or ringtone and it'll go to the appropriate folder.
From what i understand this should work for all android OS including the hero which I've used and it works
enjoy
info app