Recently my car begins to shake when I brake. Its not that bad of a shake, more of a rumble. What can it possibly be? Rotors, Alignment, brake pads?

 

Your rotors could be warpped.... id start off buy having the rims balanced.. then alignment if that doesnt fix it Get new rotors or have them resurfaced... if that doesnt work try to think if u hit anything in that case a tie rod could be bent (worst case scenerio)

 

warped rotor

 

Sounds like a warped rotor to me...

 

either pad transfer or warped rotor..

go do a pad bed in (10x 100km-20km stops with a long cool down without stopping totally)

if that doesn't fix it then get your brake shop to skim the rotors, then rebed the pads