I'm still working on this myself but this is what works reasonably well: I coat the tofu with cornstarch and use a non-stick pan with a bit of oil over a medium high heat -- don't try to turn until you're pretty sure the bottom is browned. It's tricky to get it really crispy like I get at Asian restaurants but that's what works for me, more or less :)

I also always use extra-firm or firm tofu that I've frozen first, thawed, and lightly pressed. I generally freeze my tofu first because I like the texture it gets from freezing and thawing.

My understanding is that deep-frying probably yields the best results for crispiness but I haven't tried that yet. I might have to get out my wok and try it next time.

I love nutritional yeast -- do you use that to coat the tofu?

Here it is years later but - yes, I coat with nutritional yeast. Also use it in soups too. Thanks for your help.