Praise Him with Midi has MIDI downloads for many praise songs, including Ray Boltz, Michael W. Smith, etc.
Cakewalk produces some good MIDI/audio sequencers.
NoteWorthy Composer is a software music composition and notation processor for Windows. It allows you to create, record, edit, print and play back your own musical scores.
Audacity is free, open source software for recording and editing sounds. It is available form Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems.