First up was Good Mail Day by Jennie Hinchcliff and Carolee Gilligan Wheeler.
From the publisher Quarry Books:
"What is a good mail day?” A good mail day is a day when, instead of just bills, catalogs, and advertisements, your postal carrier delivers artful, beautiful, personal mail from friends and acquaintances all over the world. Mail art is a collaborative art form with a long and fascinating history populated by famous artists as well as everyday practitioners. The term “mail art” refers to pieces of art sent through the mail rather than displayed or sold in traditional venues. Mail artists often use inexpensive and recycled materials including postcards, collage, rubber stamps, and photocopied images. Mail art is a truly international activity and a fun way to connect with people in every corner of the globe. Readers will learn to create decorated and illustrated envelopes, faux postage and artistamps, find penpals, make a mail art kit, and much more!"
Mail Me Art by Darren Di Lieto.
From the publisher How Books:
"This inspiring book showcases the 200 best illustrations from the Mail Me Art project (http://www.mailmeart.com/) --a popular online designer challenge to create a piece of art on the outside of an envelope or package and send it through the mail. You will enjoy the variety of unique art produced by artists around the world and will be inspired by the challenge of shipping art through the mail. Interviews with sixteen of the illustrators included in the book offer insight into the process and challenges of creating the art. "
(Over the Counter is a regular feature at A Bookworm's World. I've sadly come the realization that I cannot physically read every book that catches my interest as it crosses over my counter at the library. But... I can mention them and maybe one of them will catch your eye as well. See if your local library has them on their shelves!)