[n00b on demand]

I want to change my brake pads (all 4) just as general maintanence as its been 2 years since they have been done. With the way I brake I know they are probably worn out plus i can hear a very faint squeal. So where can I purchase the cheapest pads but also good quality? I have worn out rotors too as I get vibration when braking...been like that for a while now. I would like to buy all at once ( pads and rotors) but don't have the funds right now to do so.