just replaced the engine in my 93 toyota pickup, 3.0 with an manual tranny, have a coolant leak some where probaly just a hose loose some where, but it only leaks after i have parked and its has been sittin for about a half hour, that kind of has me baffled? any ideas

Where is it leaking from? Is there a puddle?
Leaks can come from anywhere in the cooling system.
Some autoparts stores rent or loan tools. See if you can get a cooling system pressure tester. It looks a little like a bicycle pump. Pressurize the system and see if you can find the leak.
Look for water stains that may help to identify the leak.

Pressurize the system and see if you can find the leak.
Look for water stains that may help to identify the leak.

2 very good suggestions.

Check around radiator and heater hose connections, all around the water pump, freeze plugs in the block, and with the 3.0 could even be a intake manifold gasket problem.