Haha, that sounds absolutely gross. I've been to a few dissections myself, but they've always been old people (thankfully) with no acne whatsoever. And we haven't cut anyone's faces, anyway. Do you think it would be useful to find out what a cross-section of a pimple is like? I don't really see how it would matter, though I suppose it's quite interesting. People who do autopsies or dissections for a living would probably know what pimples are like if dissected, even if they don't intentionally dissect acne.

And oh, to your actual question. Yes, there are dissection videos online that you can watch, although I don't remember any urls right now. You should be able to find them with some research. I doubt they would be dissecting pimples though. I haven't checked out the online material, but I always thought they tend to focus on anatomical structures and such for educational purposes.