American Quilt : A History of Cloth and Comfort 1750-1950;
Roderick Kiracofe - This is a wonderful overview of quilts in
America. It also has a lot of information on how to identify
the era a given quilt is from.
Communion of the Spirits : African-American Quilters, Preservers,
and Their Stories; Roland L. Freeman - This book traces the
stories of a number of African-American quilters and their quilts.
It's wonderfully informative and has some beautiful quilts.