engine will not rotate

[cre]

Originally Posted by cre

Pull the spark plugs and check for anything inside the cylinder which could be getting in the way... such as a valve. Have someone using a flashlight watch to see if the pistons are moving while you try to turn the crank. If the crank turns without the plugs in you're just fighting with the compressing air.

A thrown rod doesn't always come out the side of the block. See if the pistons are all moving, even just a little and make sure there's nothing in the cylinders. The starter being seized is a definite possibility, same for a jammed clutch (if it died in a VERY bad way ) and a seized transmission.

Pulling the starter is the best way I can think of. As for the clutch, there's an inspection plate on the bell housing you can pull off to take a look inside. I presume the transmission's not the issue as I assume you had it out of gear when it was towed?