Seeking MIDI Maker

[Sir Toaster]

I'm looking for something that will let me make MIDI files. Preferably some kind of keyboard program where I press button X to make note Y on instrument Z, and preferably freeware/open source.

Google has repeatedly failed me, so I thought I'd seek help here.

Apologies if this in in the wrong forum, but it sounded like the right one.

[ZKB]

Umm..Jazzware is free and open scource, but it uses standard MIDI sounds.