Bought a non-working '02 Liberty, where to start?

The car doesn't start, makes a click thats it. When I had it towed to my place, I noticed oil was leaking from the bottom. My tow truck guy thinks the motor's completey blown, I'm hoping it's just the starter and the oil gasket. Battery is fine, I am going to check for error codes in the morning. The car has 157,000 miles and has never been in an accident. The original owner told me the car just stopped on them. Would like advice on what to look for to see if the motor's completely blown or if it's something less serious. Thanks in advance to all replies.

Use a deep socket and a 1/2 drive long ratchet or breaker. Install the socket on the bolt at the end of the crankshaft. If the engines turns over it's not locked up and should start. If it turns check the relay for the starter you can swap out and if it starts purchase a new relay. If it leaks more than a quart a week fix the leak.
Check the oil before trying to start.

I finally made my first attempt to turn the engine, here are the results, interested in your opinions/verdicts:

1) The engine rotates counterclockwise (standing from the front of the vehicle) very well. When I try to rotate it clockwise it will go for perhaps 1/8th of a turn then get stuck. I was told it should rotate CLOCKWISE from the front, so please let me know if that's right or wrong.

2) I heard a noise inside when I rotated the engine counterclockwise, almost like a loose nut tumbling around, I heard it twice, that's why I'm mentioning it.

So let me hear it, good or bad, so I know what to do next, and thanks in advance again for all replies, you guys have been great!

Use a deep socket and a 1/2 drive long ratchet or breaker. Install the socket on the bolt at the end of the crankshaft. If the engines turns over it's not locked up and should start. If it turns check the relay for the starter you can swap out and if it starts purchase a new relay. If it leaks more than a quart a week fix the leak.
Check the oil before trying to start.

UPDATE: It seems that actually the engine rotates in both directions, but there is a "range of motion" after which it stops. While i was trying to rotate the engine counterclockwise to do a cylinder test, the engine actually got stuck as well, and strangely enough I tried going the opposite way and I was able to turn it a few times. Let me know if that means anything, thanks in advance.

Update:

I talked to a few people and the consensus is that if the engine rotates both ways but the range of motion is limited, that more than likely it's just a timing belt, and as long as there is no valve/piston damage the engine should work after the timing belt replacmeent. Would appreciate your feedback as well, thanks in advance for all replies.

http://www.ebay.com/itm/251578942595/www.ebay.com (http://www.automotiveforums.com/vbulletin/www.ebay.com)

http://www.ebay.com/itm/251578942595/www.ebay.com (http://www.automotiveforums.com/vbulletin/www.ebay.com)

I don't think that's going to work I have a 3.7L V6 :headshake

http://www.ebay.comhttp://www.ebay.com/itm/191338362417/
It appears you have a timing chain I would check for a broken guide.
I thought you said you have a timing belt.