Hex Editor: HxD
http://mh-nexus.de/en/downloads.php?product=HxD

MIDI Maker/Editor: FL Studio (Demo)
http://flstudio.image-line.com/documents/download.html

Other Useful Links:
Creating Music With FL Studio Demo (PokeCommunity Forums)
http://www.pokecommunity.com/showthread.php?t=215852

Obtaining MIDI Music from other platforms (PokeCommunity Foruns)
http://www.pokecommunity.com/showthread.php?t=228003