My mother has a 1995 Honda Accord EX sedan. When it rains, the drivers side where your feet are gets damp/wet. I don't even know where to begin finding the leak - is it coming in from the sunroof, the door, the windshield? Any advice appreciated.

 

I'd suggest drying out the interior. Use a garden hose on a suspect area, then check if the floor is wet. Lining the floor with newspaper can help you see when water starts entering the car.

The sunroof, windshield, driver's door are the three places I'd start.

 

I'm with cleaning the drain tube(s) and being sure they are clean and connected......pretty common with these. There is a "connector" the tube from the roof goes into where it then goes thru the body to drain. It can and will clogg and sometimes cleaning will get it, other time the tube will have already pushed" out of the connector, means you have to re-insert it.

While you are checking the drivers/left side you might as well check/clean the right/pass side drain.