If you replaced the starter an solenoid already and all your getting is clicking from the solenoid, then I would say your not getting enough juice from the battery. Start by cleaning the battery terminals and connectors with a wire brush until they are shiny. Inspect the wires going into the connectors to ensure they aren't corroded. Also check your negative cable where it connects to the frame and body to ensure they are tight and have a good connection. After all this, if it still just clicks, than the battery is probably history. Get a jump start and then drive it to a local auto parts store and ask them to test your battery and charging system. Most will do it for free.