Quick couple answers for you:
1: Printing on some medium and mounting it to metal
2: Prep your metal surface (sanding, other), print your image on transparency film. Coat your metal surface with something like Purel (you are doing an alcohol based transfer) and apply the transparency, wait X amount of time and remove carefully.
3: Use something like Dass Supersauce, or InkAid - print onto a transfer film, follow their direction. Bonny Lhotka is a great teacher, if you go to DassArt you can get up to speed pretty quick. You want to have a pigment based inkjet to be successful with these methods (2 and 3)