Only thing you need to get is a nice drum machine VST and some good drum samples.
Sonars drum vst is more for live sounding drums etc. I mean, you can do stuff with it, but you need some hip hop samples.
You can find some hip hop sounds in some of the softsynths that come in sonar if you start digging in and searching them.
I recommend native instruments Battery, the latest version of course, and some good hip hop samples.
Other than that, X2a is going to have a lot for you to work with.
You can always just place drums in the track view too if you have some good samples like Roland 808 and 909 sounds, just good kicks, snares, hats etc.
It is nice, and also standard to play drum parts though, and a vst drum machine (I'm talking software that you control with your keyboard controller, or any type of midi controller with keys or drum pads)