I manage to get a bonus game and got a wooden tile. What do I do with it?

You can put them into your Tile collection or sell them to other users ^_^ Most of them are worth a nice amount of sP :)

Tile collection? is there a place in the game menu to put them in? I searched and saw nowhere to put it.

At the top it says High Scores-Tile Collection. Click on tile collection. You should be able to put it into your tile collection. There's achievements and prizes.