Freeware Delusion or Hammerhead. Pretty basic and sound is not all that great but can get the job done.
Delusion allows you to change the tone, attack, decay and punch. Hammerhead is you get what you get in sound.
Both work on a straight 16th note "button" method to place your beats. So you can't really do much with triplets unles you adjust the "swing". this effects the whole loop not just a single "track".
It's good for something free/opensourced to get you started until you are able (or want) to go purchase a good drumtrack software.
I tried uploading some test tracks lastnight. failed but keeep an eye out this week for some test tracks I will be posting. It has the "Delusion" drum software for the beat.
[FONT=Comic Sans MS]I reject your reality and substitue my own[/FONT]
[FONT=Comic Sans MS]BYAAAAAAAAAAAH![/FONT]
[FONT=Comic Sans MS]But it goes to eleven....[/FONT]