Re: BAD soil, BAD!
I have the same problem as you. My garden was rock hard clay with zero nutrient levels. In the fall of '07 I brought in about 10 yards of horse manure and covered the garden 6" deep. The early spring '08 that was rototilled as deeply as possible and another 10 yards was brought in and tilled as deeply as possible. Now, a year later I can walk out there and push my bare hand down into the lush dark soil. All the soil on this property is clay with zero nutrient levels so I am seriously contemplating redoing the lawn in the same manner as the garden, only not tilling quite so deep.
You can use any manure that you can get in bulk quantities, whether it's fresh or composted. By the time you mix it into the soil it will be so diluted that it will not be able to generate enough heat during decomposition to harm neither seed nor sod. The only time that fresh or "hot" manure is an issue is when applying it directly to a plant, that is when you can burn the plants.
Sand may or may not be necessary, IMHO it's not needed with sufficient application of organic matter, particularly if you're on a budget.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!