Gothorita (IIRC) is still going on. You need a special code found in the Pokedex Strategy Guide for Black 2/White 2. If you participate in the Pokemon TCG leagues you can get special Pokemon for just attending. The current (first one) is Scizor, I think it ends soon though. You can get a special code for purchasing the Black 2/White 2 Game at Walmart to get one of the Sinoh Starters (Piplup, Turtwig, or Chimchar).
Of course then you can go to the Dream World & meet Pokemon to take back to your game.
Are the gothorita and TCG Pokemon limited time only or are they forever?
The Walmart promotion is in specially marked packages of the game and ends in April or whenever they run out of games to sell. As far as DW Gothorita's concerned, the second game guide doesn't mention a date but Dream World might.
With regard to the pokemon TCG leagues, Scizor's already been handed out; Cloyster gets handed out tomorrow if you attend the winter regional. If you miss any of them I'm sure there will be people trading them on the trade boards.
Official Cresselia of B/W2 Boards; Official Darkrai of PMD: Gates of Infinity Board
Or I'll just use my action replay lol. I swear Pokemon is the only justification to use an action replay. But still I want as many things legit as possible. Thanks though! Anything special about these TCG Pokemon?