Hop David (yes, that's a real name, not a funky dance) is very possibly the best living tessellation artist. He's recently had two slim childrens' tessellation coloring books printed with Dover Coloring Books, who print a very wide variety of art coloring books for very reasonable prices-- about US$4 each. The easily understood line drawings are based on Hop's best artwork. Read our review of "Magic Mirror Image" or go directly to the ordering and comments page for Magic Mirror Image Coloring Book and Geoscapes Coloring Book on Amazon.com.
One book which David Annal, the original webmaster of Tessellations.org, recommended above all others was written by a quilt designer, not a mathematician. She began at the beginning and investigated it all from scratch. As such, it is easy to understand and full of diagrams and lavish illustrations -
'Designing Tessellations' by Jinny Beyer (ISBN 0-8092-2866-1)
The reference book for M.C. Escher's work together with classification and discussion of the symmetries involved is -
'Visions of Symmetry' by Doris Schattschneider, professor of mathematics at Moravian College, Bethlehem, Pennsylvania, USA. (ISBN 0-7167-2126-0)
A highly recommended, very accessible full-color "do it yourself" tessellation book written entirely in French -
'Parcelles d'Infini: Promenade au jardin d'Escher' by Alain Nicolas. Read our review of 'Parcelles d'Infini' or visit the website of this French language tessellation book. (ISBN-10: 2842450752 ISBN-13: 978-2842450755)