We had a wonderful fishmonger (sadly, he died far too young) who got us into fish in a big way. From being scared of a piece of raw fish and not knowing what to do with it a few short years ago, I now cook many different kinds, and you're right, the more you do it the more confident you get. The biggest mistake possible is to overcook it because you're scared of it being still raw in the middle. Only the very thickest hunks of fish need more than five or six minutes, and thin fillets need a lot less.