Thanks! I make most of my music in a program called Mixcraft 6, but some (like Sarin's Theme) were made in Garageband on the iPad using a similar tactic. I do have some handplayed Garageband songs, but they're mostly three notes over and over with different octaves or whatever (I don't know what proper music terms are, meh...).
Anyway, I'm glad you like them! I'm hoping to add more sometime!