I don't know anything about what file formats for music that can be read and played by Gameboy libs. Maybe it is possible to convert to Midi and then use another tool for making it Gameboy-playable?
WaveBots has no direct way of exporting to GameBoy, but it is possible to write a converter from one of the supported formats into something that can be interpreted by a GameBoy game. I don't know of any such tools myself, but it might exist.
