I had the same problem this fall. They got in through my gable vent...chewed a nice hole and just made themselves at home. After contemplating shooting them...I called the exterminator. Here's what they did.....they covered the vent with some heavy wire screening, except for a small section where they attached a 2 foot length of 6 inch PVC with screws. The PVC was pointed down towards the ground and the end of it was baited with peanut butter. The squirrel leaves the attic and goes into the PVC after the Peanut butter and slides right out and onto the ground. They can't climb back in because of the smooth surface. After about a week and no more noise in the attic....they're gone. remove the tube and cover the vent with more screening.
Believe it or not.....it worked like a dream. I could have done it myself and saved about $150 if I knew what they were going to do....oh...they charge to remove the tube too....I did that part myself. Good luck
