If its not even cranking or turning over the first step like Damir said is the starter. In the past i have pulled the starter hooked it to the batter and hit the starter to see if she spins, if not there's your problem. If it does it could still be the starter, those starters are little DC brush motors they get a lot of carbon buildup and lose efficiency and will still "try" but cant quite put out the power to actually turn the gears.

Have you tried bump starting?