How tiny is tiny? Depending on how big they are, you could go anywhere from small mysis to silverfish.... Ghost/feeder shrimp would probably do well as food, as would small live fish. If you can, getting baby live fish, such as postmeta clownfish, or newly hatched Banggais, would probably be best (assuming they're super tiny , as in less than an inch). Unforunately, you probably won't be able to find any of these...so go with marine guppies or mollies. Get them eating, and then slowly convert them to frozen food on a stick. Adult brine shrimp might work, as might large amphipods. Wet Web Media has some good articles on them. They can eat anything their size, so once some start getting bigger, be prepared to either move or lose some of them due to cannibalism.
No experience keeping these little guys, just a lot of reading up on various fish, including frogfish.