MAME – Where to find game specific button combos?

There are a variety of games I have in MAME32, but for some of them I have no clue what the button combos are supposed to be. I get a rudimentary understanding by using the TAB key to see which buttons go to player 1 or 2. But I need the information from the front of the consoles, where it describes what each button does and what certain combinations of actions will do.

Is there a repository of such information? I have been to a few ROM sites, but didn’t find anything useful. I found user manuals, but those were for setting up the equipment, not using the games.

Specifically, I’m looking for “The Punisher” and “Street Fighter 3 Alpha”, but would like more if possible.