For simple isometric playfields I'd use two tile layers, one for each row of tiles.
Each tile is a graphic in a diamond shape so they can be linked as you'd imagine an isometric display would be.
The layers are then offset by half a tile, so they interlock as below.
The green tiles could include imagery that overlaps the red tiles, so you could create some pretty landscapes easily.
If you want to get fancy then you can switch the layers using line interrupts on lines that are half way through a tileset. This would mean red tiles can also be above the green.
Below are 16x16, but you could of course do 16x8 or 8x8 or use line interrupts for other smaller dimensions, depending on how you want it to look.
