The switch can be purchased at NAPA. I bought one a couple of years back. You'll need to drop the steering column to get to it. Take the covers off the column and check the rod that goes between the key cylinder and the switch to insure it is still intact and not busted loose somewhere. Have you checked the solenoid? I had that problem way back when and it turned out to be the solenoid. Soon after, I ended up replacing the starter.
Good luck!
------------------
Motor Safe!
George
75 Mustang II
94 Ford Ranger XLT 4X4 (172,000+ miles) I need a new truck!
http://members.nbci.com/UnbridldFury
http://www.pierce-county-mustang-club.org/
M&M Member #47
Madness takes its toll. Please have EXACT change!