Batter is fine, lights, radio and locks all work, makes one click sound when turning the key and the alternator was on its way out, is it a simple alternator replacement or starter? Please help

 

Its prob the starter since it wont start, try it with another battery 1st though

 

The 'click' sound is probably your solenoid. It's an electro-magnetic switch that completes a circuit to the starter motor itself which then spins the engine. Over time the contact portion of the solenoid gets dirty or worn out and causes a poor connection, so, no start. It can also 'click' repeatedly if your contacts are ok but the battery is too low. The solenoid energizes the starter, the starter draws a bunch of current which then causes the solenoid to 'let go' and the cycle continues.. click click click.
First, i'd get your battery tested and fully charged if it's good. Clean up the terminals shiny bright, then try to start it. If it doesn't start, you could make sure your starter connections are not loose, oily or dirty, and in some cases you can even whack the starter motor with a hammer to get one or two more starts out of it. Once your battery and starter are good, replace that failing alt. you mentioned. I'm wondering why you say it's 'on its way out'? Hope this helps