Quote from Sueycide_FD :

i was over at a friends house today and he has a mac. I've never used one before ever in my life so i had trouble getting around the interface, but i was browsing the apps and came across this thing called GarageBand. While poking around at it's features, i almost said "Not even better than Acid 7.0" untill i saw keyboard mapping (can't remember but it's under "window" on the top bar) and clicked it.

I suddenly could play piano notes on the keyboard . It had a wide variety of instruments from Techno drum set to trumpets. Anyone know a alternative to this awesome program that allows me to play notes on the keyboard?

I recommend you shoudl try LMMS and stagelight. they are good alternatives of garageband and will actually get your wrok done