| I think you can get some for free...just do a search. Otherwise there's all the commercial ones (Sonar, Nuendo, DP, ProTools. etc., etc.) In fact, I don't even know if they're even called sequencers anymore. Usually they'll all record MIDI and audio and be found under the heading:"digital recording". OR...check out "Band in a Box". It's a pretty cool program that will let you input changes, styles, tempos, time signatures. | 
