I have been looking for a easy to use music creator that is free and i found the perfect one..... its called Psycle here is the download page...
http://sourceforge.net/projects/psycle/files/latest/download?source=files a warning though if you want to look it up first do not click on link because the link will download the program automatically... i dont know if it works for linux i have windows 7 and it works great so give it a try i suggest looking at the help tutorial to get you started...