http://www.revscene.net/forums/69867...pots-lawn.html
^^I did a write up about growing my lawn last fall.^
Long story short, build minimum 3 inch layer of soil (65% sand/35% compost. Sand will help the water drainage/moss issue) and a bag of seed.
Use a long 2x4, get down on your hands and knees and use the 2x4 like a squeegee to level the soil.