The book has ISBN number 0-471-02865-7. It is published as part of the Wiley-Interscience Series in Discrete Mathematics and Optimization. The list price is US$ 44.95, but most booksellers seem to charge only US$ 39.95. It may be ordered by electronic mail from several booksellers, e.g. from Powell's Technical Books, Oregon, USA.
An interesting graph coloring link is Joseph Culberson's Graph Coloring Page. It contains links to numerous other sites with material of interest for graph coloring.
For general information related to combinatorial mathematics, consult the World Combinatorics Exchange.
Graph Theory by Reinhard Diestel (Springer 1997) gives an introduction to general graph theory including chapters on coloring and integer flows.
Digraphs: Theory, Algorithms and Applications by Jørgen Bang-Jensen and Gregory Gutin (Springer 2001) is a comprehensive text on directed graphs, containing material on the relations of graph orientations with coloring and integer flows, and with discussion of directed graph homomorphisms, among other topics.
