Hey I Had the exact problem not too long ago.
I changed the starter/solenoid still no start.
It was my N.S.S (Neutral Safety Switch) I didnt even replace it i just tapped on it a little and cleaned it off, works great now.
If tapping dont work you may have to remove and take it apart there is a good post somewhere out there with good info and pics, just search the forums on Nss r&r.
If that doesnt work it may be your ignition.
If you want to test that you can check if you are getting power from your ignition at the starter with a voltimeter if your getting juice all is good if not then look above just to narrow it down.