Youll have to remove the hub to replace it, that is the hardest part, use a punch and a big hammer to drive out whats left of the broken one, you can usually get a single lug nut and stud at a tire shop.

Your hub comes off after you remove your lock outs or drive flanges, there is a bolt attached to your CV half shaft, then a 54mm lock nut, followed by another, hub slides off, unbolt your rotor, pound it out, hammer new one back on (need new front brakes? now is a good time to do it <img src="/forums/images/graemlins/smile.gif" alt="" />) put everything back on in order, it would probably cost $30 for somebody else to do this if your not comfortable with it.

Only specialty tool youll need is that 54mm hub socket or the equivalent standard size (2 1/16th i think)