The following spaces are empty in my pokedex.
Where can I find trainers who own them or where can I get them in the wild?
GO HERE, Search for any Pokemon, go to the near bottom and it will tell you the locations of that Pokemon! It's easy as that!
Tropius- Route 18
Carnivine- Route 18
Rufflet- Can only be found in Pokemon white/white 2 so you have to trade.
Skitty-Can only be found in white 2 so you have to trade.