My list would include:

Best all-around garter snake book:
Rossman DA., Ford NB., & Seigel RA. 1991. The Garter Snakes Evolution and Ecology. University of Oklahoma Press. Norman, OK.

Best intro to garters:
Bartlett RD & Bartlett P. 2001. Garter and Ribbon Snakes. Barron's Educational Book Series, Inc. Hong Kong.

Best Care and Maintenance book:
Perlowin D. 1994. Garter Snakes & Water Snakes. Advanced Vivarium Systems, Inc. Lakeside, CA.

Best non-garter snake book:
Ernst C & Zug GR. 1996. Snakes in question. Smithsonian Press. Washington DC.

Book I'd most like to see in English:
Hallman M & Chlebowy J. Strumpfbandnattern.

What are your favorites? Make up any categories you'd like.