Try Fruity loops studio or better known as FL Studio.

search it up on youtube. they got all kinds of tutorial for any genre.
whether u want to do hip hop or trance, this software does its job the way you want it.

it doesn't comes free though. But as the saying goes, "If you want something badly, work for it!"

But come on, who would want to pay that much to use this magnificent software? people are making big bucks using this software without paying. And I know many producers who does this.

tell you what, try the Demo trial version first. If you like it, invest on it. don't try something stupid like downloading by torrent cos they always have viruses packed within the file.
I know i did and i learnt my lesson.

dr dre uses pro tools
he has highly skilled musicians create intricate beats with midi instruments because hes rich
big time rappers like dre dont use sequencers