Don,

Connect a test light to the terminal on the solonoid that is connected thru the wire to the key switch.

If the light does not illuminate when you turn the key to the start position, the problem is in the key switch, the wires or one of the connections between the key switch and the solonoid

If the light does illuminate and the starter doesn't work, the problem is in the solonoid or the starter.

This should give a place to start looking to fix your problem.

P E H