it's pretty simple to get started, there are some sick plugins that can do everything from making 4 to 8 way stick switching a snap to lighting up LED buttons to show what buttons do what in each game.
It can be used to make simple utilitarian layouts, or bad ass animated showstopper layouts.
lots of expert arcade builders use or have used it (daoldman, drventure, LeChuck, and many many more), so there is a nice network of giants on whose shoulders you can stand.