sansa e130 won't go past 'creating music library file'

Most likely one (or more) of the files has an ID3 tag that can’t be read by the player during its database refresh. Get the free MP3TAG software and set it to write format ID3v2.3 ISO-8859-1. Open up your files in it (from the computer, _ not _ the player) and re-save them in this format. Also check that there is nothing in the Comments field and edit out any strange or foreign characters anywhere. Save and delete the files from the player and then transfer over the newly edited ones.