pulling to the left/right is normally:
1. tyre pressures
2. tracking/camber adj out
3. tyre rotation incorrect
4. pressures
I would say that a binding caliper might add to the sensation of pulling, but not always true. Best bet is to put on a brake roller (at a MOT garage for example) and run up the front axle. This will show if brakes are binding or not. As for steering geometry, get it done by a professional. I get loads of cars 'done' by tyre fit companies and most are wrong!! Also - dont forget the camber of the road. This can also dictate the 'feel' of the steering wheel.
Any doubts/questions, feel free to PM me!
Regards
Reuben
0208 681 0208
http://www.tuningwerkes.com