I always shop at Gosselin. They don't often have the expired stuff, but when they do, it's pretty good. Last time I got a few rolls of Ilford Ortho for 12.79$.
I don't know if they still do that but I know FlicFilm used to sell roll ends for a good discount too. I have a roll of ATM400 with somewhere between 30-36 exposures on my desk right now. I just have to find the time/weather/occasion to run it through a camera.