If I use Pokémon Trader or Energy Search and there aren't any Pokémon or Energy in my deck, do I have to show my deck to my opponent? If there isn't any in my deck, do I get to put the Pokémon Trader or Energy Search back in my hand either?
You don't have to show your deck and you don't put the trainer back in your hand [Ed. note: It goes into the discard pile].
Source: WotC Chat (2000-08-17)