Most all the soils I have seen in Pennsylvania are clay soils, that is the soil you will have to work with. Start, as with any good organic method, with a good reliable soil tests. Contact your local office of your Pennsylvania State University USDA Cooperative Extension Service and inquire about having a good, reliable soil test done so you know what your soils pH and base nutrient levels would be so you can make good decisions about what needs to be done that is both good for you and your environment. Then dig in with these simple soils tests,
1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

which will help guide you in making the soil you have into a good, healthy soil that will grow a strong and healthy lawn.

Here is a link that might be useful: PennState CES

Thanks, kimmsr!

Organic can be expensive (if you buy compost) or it can be on par with chemical fertilizers. If you look at the ingredients in organic fertilizers, you will find you can buy the same ingredients in 50-pound bags at a feed store for about 1/6 the cost of the commercially bagged ferts. I like to use ordinary corn meal as a fertilizer. Some years I'll use alfalfa pellets (rabbit food). Many people use soy bean meal. If these materials are all you use, then the cost is on par with chemical fertilizers. Compost is the material that can really eat a hole in your wallet. It is very valuable. If you have a source where you can get excellent compost (stuff that smells incredibly fresh) for something in the neighborhood of $20, then go for it. The application rate is 1 cubic yard per 1,000 square feet. Fall is the best time to apply it...at least that's what Mother Nature thinks.

Here is a link that might be useful: Organic Lawn Care FAQ

Thanks. I live in a pretty rural area so I have access to some feed stores...I'll check them out. I also have a couple rather large piles of wood chips from some trees I cut down about a year and a half ago...there's probably some nice compost in the bottom of those piles :)

I drive 20 miles, past several feed stores, to find what I'm looking for. Of course one thing I'm looking for is a locally owned feed store (not a chain).