Preemergent weed controllers will also control your new grass seed. You can't really do both. I know you did not want to hear that.

You don't need to feed the lawn in the spring unless you have a baseball diamond. Scott's really has people fooled into buying their products. Wait until your grass has been mowed for the second time at least before fertilizing. Preferably wait until Memorial Day. Most grass really needs fertilizer in the fall, not spring. In the spring it will grow faster than you need anyway.

Minimize crabgrass by keeping the grass as dense as possible. This might mean reseeding every fall until you get it dense. It definitely means mowing very high to help shade the bare soil between fescue plants. Many people like Kentucky bluegrass lawns because they naturally grow very dense while fescue naturally grows very thin unless you used more seed than most people.

Also minimize crabgrass by infrequent watering. Crabgrass seed needs moist soil for a couple days, so if you can only water once a week that will give the soil time to dry out and the crabgrass will not sprout.

Unfortunately you get both good and bad advice on forums. dchall is not totally correct. It's true that broad spectrum preemergents like Dimension will stop new grass seed from germinating, but there is one you can use to prevent crab grass from germinating and is harmless to grass seed, it's called Tupersan (registered name) or siduron (chemical name), and it is often applied at the same time as seeding. Personally I don't like fertilizer/weed controller combinations, you are much better off buying fertilizer and a weed control product and applying them seperately. I also don't agree with not fertilizing in the spring. Most turf professionals would agree with this too. It is a bad idea to provide too much nitrogen in the late spring/early summer, and dchall's advice of a Memorial day fertilization is wrong, especially in Georgia. This can lead to a higher probability of lawn disease. Also mowing very high, especially for fescue in Georgia, will increase your chances of fungal diseases. I agree that deep infrequent watering is advice for any lawn, but let's face it, weeds have evolved to germinate and grow with what nature gives it, and they are very good at it, so good watering practices will have little effect on them. Your local extension office should have some good advice for your area, so don't hesitate to give them a call.

You also get the wisdom of the ages and people who might not have the same experiences. The advice I gave is based on years (and years) of reading and moderating forums for amateurs and professionals. Applying fertilizer on Memorial Day might be too late in your area due to the onset of summer heat, but as a starting point, it is a very easy date to remember. Whether you get disease or not depends also on grass variety, air circulation, dew, humidity, soil type, and other factors. I'm not sure why Georgia would be much different from other places where the taller grasses are the healthier ones.

At the same time that the wisdom of the ages sounds like a good idea, you also get the senility of the aged. Tupersan is relatively new to my repertoire of garden products. I became 100% organic before I heard of it and seem to have a block about that product. In general I don't put any faith in preemergent herbicides but people I respect tell me they work. I do recall from my relatively recent reading that Tupersan works as tiemco says.

Professional grass growers (livestock producers) fertilize with 1/4 of their annual nitrogen in the spring, and they always apply it after the initial flush of green growth has ended. They apply 3/4 of the annual nitrogen in the fall. They do it this way to minimize their mowing workload and to spread the productive growth along throughout the entire growing season.

The wisdom of the ages here at GardenWeb also agrees with tiemco that combination fertilizer/weed killer products are not going to do what you expect them to do and it is better to use different products for the different requirements.

Yes Mother Nature has Her own ideas about watering, but for what you do, you do not have to encourage weeds. Far too many people set their sprinkler to operate for 10 minutes every day. That schedule is going to germinate every seed in the garden. You have control over your own watering. Allowing the soil surface to dry out as much as you can will develop deep, drought resistant roots as well as minimize weed seed germination.

Well, I appreciate both of your thoughtful responses. Thanks.