Starting to think towards first term next year. We are preaching through Isaiah across all of our services, and I will be writing the small group studies to go with the sermons.
I have the following commentaries:
Webb (BST)
Motyer
Oswalt (NICOT)
Any others, or other resources that I should get my hands on?
In Anticipation 
David Peterson's book, Christ and His People in the book of Isaiah, is good for chapters 6-12.
cheers Gary!