Thanks for your help.
Incidentally, I've done lots of 'simple' Google searches and there seems to be lots of different programs out there that do the conversions. Knowing how to use the software is another story. I've downloaded the sunfly files and each song is split into two files (yes, I've researched this). I'm struggling to feed the files into the software so that it becomes one zip mp3+g file at the other end. I don't want to play it on my pc, I want to load up an SD card.
Thanks again