It is relatively easy to make your own hammock and if you make it double layered you will have pockets below the first layer where you can place a sleeping pad. This will give you enough of a layer underneath, so you do not need a quilt. In summer, (June/July) you would not need an underquilt. Just hang a layer, like a ground cloth, underneath the hammock just to block a draft. Look up "Speer Hammocks" You can find how to make your own. It is possible to do so without any sewing.
http://hammockcamping.com/
Here is the double-bottomed hammock MYO:
http://www.imrisk.com/zhammock/zhammock.htm
I have sectioned hiked the AT end-to-end over three summers, all in August. The trail divides nicely into 100 mile sections. With the exception of hiking south from Killington to the MA border, I hiked north. In August, the southernmost section is filled with AT thru-hikers. You can learn a lot from them. The most important thing I learned from them was that I had the ability to hike at a faster pace. I learned to increase daily mileage.
In the AT/LT section I often stayed at shelters, but not in the shelters. I used a hammock which meant I could sleep most anywhere, no longer needing flat or non-rock ground, just two trees.
Hiking the AT/LT , I had a lot of rain and mud, but I got used to it. However, not having dry feet meant blisters, but I have learned to prepare better and have had little problems since.
Hiking the sections north of the AT meant fewer people, even finding myself alone in shelters. I stayed in many shelters north of the AT.
The Green Mountain Club in VT offers workshops on hiking the AT given by thru-hikers usually in early June or May. Buy the End-to-Enders'Guide" from them, too. (greenmountainclub.org) Here is another new site about the LT:
http://www.longtrailhiking.info/
Of course, if you complete the AT you will have hiked 100 miles of the AT, too. So, it is inevitable, you will start hiking all of the AT.