Randomly Generate Tiles made from Different Sprite

So I've seen the following tutorial which talks about randomly generating tiles that are all in one sprite:

scirra.com/tutorials/360/generating-a-random-tile-map

What I would like to do though is generate a grid of random square tiles (e.g. 4 way intersections, 3 way intersections, etc.) that are all their own sprites.

I gather arrays would be useful in this, but I'm just not sure exactly how to go about it.