Solenoid?...
It may be your solenoid. What you can do is take two screwdrivers or any other heavy gage metal or wire and jump from one lug to the other of the solenoids heavy gage, red wires. If the starter turns over, it's the solenoid. If the starter does nothing, it's the starter.
Most of the time, its the solenoid. If your not familar with that procedure, your going to see a spark arc when you bring the metal of the screwdrivers together. :cheers: