Originally Posted by puritansound

I make my living as a Master Gardener...don't get to excited yet -theres a whole lot I don't know. The brother who posted that a lot depends on where you live in the country is absolutely correct. I am in Michigan and cold weather species of grasses are a bit differn't than the southern varieties. Where do you live? If it's in the North I could give you some tips, but if its the South, it's out of my element.
As to testing, it would help to know what the nutrient make-up of your soil is...but the report is going be limited to nutrient info and recommendations on how to make it more "balanced". What won't be in there is what else may be in your soil that is causing your seed not to germinate. Your local county extension has these tests (here they are $8 per test). They also probably will have tips and suggestions on growing a healthy lawn.
Pre-emergents are a great way to get a hold on weeds. But be aware that they stop everything from growing (that includes grass seed). Most of them work 6-8 months. the reason for this is that crab grass, for example, germinates in the spring but does not emerge until late summer, generally speaking. If your pre-emergent is down and you try to grow grass -it won't grow.
It is normally to hot in summer to grow seed. It is hard to keep wet. Spring is the best since it is normally rainy and fall is good because it cool (the water does not burn off rapidly).
If you live in the North let me know and I will give a you a plan of attack for the rest of the year. But at any rate, use your local extension. Your taxes are paying for it.