clicking sound every time press brakes

I purchased it in 2007 with 46,000 miles. until 11/10, i drove only city miles; 5-10 miles a day. in 11/10, i moved & i now drive highway miles. there's a clicking sound every time i press my brakes that lasts until i come to a complete stop. the heating blows cold, the ac blows hot; the oil light keeps coming on when i know i have oil in the car; there was a loud, bubbling sound as i was idling at a red light. any ideas what might be wrong or what it would cost to fix? in august 2010 i got all new brakes, rooters, brake pads, etc. but i feel like they're grinding. is it possible i need new brakes again?

Love the site :-)