I took a mini-course with wild mushroom experts and all I learned was not to eat any wild 'shrooms. The 'experts' who hiked with us couldn't even agree on what was safe or not ... so I'm very wary. They are a fascinating life form. ;)
There are several fascinating shrooms that pop up in the very early autumn, but I don't see them every year. One is as big as a dinner plate, some are bright red.
The only mushroom I'd ever eat would be a morel, since I'm confident I know what they look like. But I've never found one, so I'm safe so far! All the ones I've eaten have come from Whole Foods.
While I love mushrooms, and eat lots of them, I'm not really fond of the exotic ones. The morels I bought I didn't think were all that. Shitakes are rubbery, as are most exotics. I like baby bellas, with just a little truffle oil.