Aero engineering has lockers, I dunno about any other faculty. If there are pharmacy lockers and there is such a policy, that means just shove your padlock on there first day you're in.
I've never really understood why anyone would want a locker at uni. The places are so big, that the time it takes you to go from one place, back to your locker, and then to the next places is more than the ten minutes given to you to get to any class. It's not worth it, IMO.
vet has lockers and its first come first serve except the 3rd and 4th years get bigger lockers since we have to store all our scrub and post mortem gear as well as our lab coats.
For Pharmacy you'll need lab coats frequently, so i'd suggest getting a locker, if only to avois having to scrounge a lab coat on days when you forget yours.
Ours are only $10 per semester, so i'd imagine yours would be similar. Most people jut keep their lab coats and a pair of enclosed shoes in it (for days when you forget you have prac and wear thongs.)
Best to e-mail them on cubby@usu.usyd.edu.au because the prices for deposits and hires have changed and I have no idea how much they are. Those lockers are available for hire in the Wentworth or Holme buildings. The Holme building lockers will be convienient for you as you are doing Pharmacy.
The Library has a limited amount of lockers for hire too but they are only for students with disabilities.