I've been using soil block to start seedlings. For those who aren't familiar, it's a block of compressed soil with a divot in the top that you put a seed. The advantage is mainly that the roots of the seedling grow to the exposed sides and than wait to be popped in the ground. as opposed to other methods where roots either have to grow through something (peat pots, or newspaper) or are cut (large trays of soil). The down side is that because of the exposed sides they dry out and need to be watered frequently, especially in full sun.
Mixing compost and peat about 3:1
Make a nice muddy mix
Early March: still a little cold in the greenhouse for starts 
I've just been using the 2" x 4 version that I bought and a 4" x 1 version that I made. For some strange reason the former cost $30 while the later would've cost $120. So I made my own out of some scrap metal that work well enough.
