I got this list just now from Art King at Harvest Valley Farms. If you are hosting Thanksgiving or bringing a dish, make it a better one. A local one! If not, stock up for some farm marketless days ahead. Most of this stuff will keep very well.
Here's what he has:
Blue Pie Pumpkins
New Red Potatoes
Yukon Gold Potatoes
Pennsylvania simply Swt Onions
Yellow Delicious Apples
In other words, combined with a local turkey, everything you need for a wonderful Thanksgiving dinner.
The market is 3:00 - 7:00 today. From Squirrel Hill or Shady Side, get there by taking Highland Avenue north, past Centre and Penn Avenue. Then, at the light at Penn Circle, take a left (it's one way). Park immediately on your left. You can't miss it.