Here is a sample drum track that I did using this method. It is from the Beatles song "Drive My Car".
I have found that this method creates as good or better drum tracks than the canned tracks that come with drum machines. But with this method the tracks are song-specific. You can also do some crazy stuff, e.g. I'm working up Brubeck's "Take Five" using the drum track ripped from Emerson, Lake and Palmer's "Tarkus" (slowed down a bit).
Windows XP, VISTA and probably earlier Windows
Step 1: Gather the tools...
DrumTrack (free software for creating...er...drum tracks...d'uh)
A midi file (download the following for the demo)
Audacity (free software editing audio...it's very cool)
Step 2: Fun with DrumTrack
Spend some time getting to know this really fine software. You can compose drum tracks with this. Check out DrumTrack's humanization (Song > Song Patterns > Humanization)...maybe it will make your drum track less drum machine like.
Now download the MIDI for the demo and listen to it. http://220.127.116.11/19841988/rock/beatles/DriveMyCar.mid
You should be able to double-click the demo MIDI file. If not (you don't have a player associated with mid files) try running Media Player and opening to the MIDI file.
In DrumTrack import the MIDI file.
File > Import MIDI Drum Score
Here's the catch...even though our Demo MIDI is a full score DrumTrack ignores all the instruments that are NOT drum related. Plus it assigns the drum parts form the imported MIDI to the appropriate instrument in the program.