AT thru-hike clothing/shoes

In March I would look at some Nylon Hiking Pants (RailRiders Eco Mesh Pants for example) and a long sleeve wool shirt (Smartwool Lightweight L/S Crew for example). Later in the year I would switch to running shorts and short sleeve shirt. I would go with the trail runner than fits you best (I like the Salomon XA Pro 3D but YMMV).

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/profile.html?u=Ice-axe

http://postholer.com/journal/viewGearlist.php?sid=aff4b836ec33aaceb46d133b8a49ccce&event_id=801

http://postholer.com/journal/viewJournal.php?sid=aff4b836ec33aaceb46d133b8a49ccce&event_id=801

http://francistapon.com/Travels/Appalachian-Trail/AT-Gear-List

Not A.T. specific but good info:
http://ultralightbackpackintips.blogspot.com/2011/07/video-tutorials.html

some A.T. lists here
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/user_gear_list_index.html
Not the lightest and it is 2 people but you might get an idea from their series of videos,they are currently hiking the A.T. and uploading new ones as they go:
http://www.youtube.com/user/jeeping32810#p/u/244/9tl_VzOKmXQ
http://www.youtube.com/user/jeeping32810#p/u/246/zju2dJVcV3o

http://www.rayjardine.com/adventures/2009-AT/index.htm

http://www.rayjardine.com/ray-way/Trail-Life/index.htm

I would contact Matt Edwards or hopefully he will get on and give you some advice he has a nice list from doing the trail this year and he has triple crowned.I linked his profile and list above.I am sure he would be very helpful.

Starting in March it is still a bit cool out, and can and does drop well below freezing at elevation. When i did 3.5 months on the AT I started in December so i had full on winter gear.

For a March start If it was me I would bring:
Head-Smartwool balaclava and smartwool beanie

Torso-Capaline 3 l/s, columbia l/s hiking shirt, pantagonia nano puff, stoic vaporshell. (if you get cold easily you might want an additional layer like a r1 pullover etc)

Legs-capaline 2 long johns, summer weight bdu pants, ecwcs goretex pants

Feet- Smartwool trekking socks, OR crocodile gaitors, and my zamberlan trekker boots

Hands- smartwool glove liners, ems fleece fingerless/ mittens, and or endeavor mitts

Towards the end of april- mid may i would send a good portion of the cold weather stuff home as it is usually plenty warm by then. (balaclava, cap 3 l/s, bdu pants, croc gaitors, ecwcs pants, fleece mittens) and replace with some convertible pants, and a smartwool tshirt.

I like the bdu pants because in the colder months i like having a fire, and since they are 50/50 cotton poly blend they wont burst into flames and leave you with giant holes from embers like the other synthetic options and they still dry fairly quickly. The ecwcs pants i just have because they are as durable as they come , though there are much lighter options out there for rain pants(i only use rain pants in late fall-early spring).

I think I have settled on a pair of shoes to get, the Merrell Trail Glove Cross Training Shoes. They seem to have good reviews and will give them a try.