So yesterday Beth and I went and bought some individual strips of sod to fill in the patch of yard without sod. It ended up being about 50 square feet of sod that we needed and we of course, didn't buy enough. So now we have to go back today and buy the last bit.
But the real lesson learned in all of this, is not that we need to accurately measure next time we buy sod, but rather never ever think about laying sod ourselves ever again. Laying the 40 square feet of sod yesterday was such a hassle that the mere thought of doing the entire yard made me tired. First I had to unload the 25 strips of sod that we bought, then I had to carry it to the backyard, then I had to figure out how the heck I was going to lay it. The part I did lay looked good, but it took me about 30 minutes to do that small part. So I figured 4000 square feet would have taken me about six months to lay.