2002 Mitsubishi Eclipse

Air Conditioning problem
2002 Mitsubishi Eclipse 4 cyl Front Wheel Drive Automatic 106388 miles

I am by no means a car person but I can change the occasional part. Recently I started to get pooling water on the driver side of the interior cab. After some trial and error, I discovered it is not rain and it only seems to happen when I run the A/C. I have no coolant in the water but my research says that it does not mean the heater core is not damaged.

I have had someone tell me that the A/C drain might be clogged and back pressuring into the cab. My question is this:

1) Could it be the A/C overflow? How do I clean it out?

2) Could it be the heater core? How can I know for sure so I don't have to go through the pain staking effort of removing the offending piece?

3) Does anyone have any other idea about what it could be?
August 21, 2010.

AC evaporator drain tube clogged find at bottom of box underglove box. Clean out with small wire

Aug 21, 2010.