This is a big question.  There are quite a few books about herps of
various
sorts, and they range from stellar to awful.  One particularly stellar
book
is _The Completely Illustrated Atlas of Reptiles and Amphibians for the
Terrarium_, by Obst, Richter, Jacob, et al. (TFH Publications Inc.,
1988), a
titanic red tome with brief entries on a huge variety of subjects, often
just
called "the Big Red Book".  Also, Advanced Vivarium Systems publishes a
series
of books on herp care which are widely acknowledged to be thoroughly
excellent; most of them are slim white paperbacks that cost five to ten
dollars (US).  They are sold in pet stores, especially those that
specialize
in herps, in both the US and Europe.

There are several periodicals devoted to herpetoculture (and many
academic
journals dealing with herpetology); these include the _Vivarium_ (the
organ
of the American Federation of Herpetoculturists), _Reptiles_, and
_Reptile &
Amphibian_.  There has been an outstanding publication called _Captive
Breeding_, but there are rumors of its demise.  This FAQ takes no
position
on the relative merits of these publications; all of them have printed
good
stuff and bad stuff, and it's a good idea to seek independent
confirmation
of any information before entrusting the well-being of your animals to
it.

All the above print resources are in English.  Other languages have
their
own bodies of herpetocultural literature; the author's familiarity with
these
is extremely limited, and suggestions for important sources---especially
the
high points of the large body of German literature---are solicited.

Local herp societies are valuable sources of knowledgeable people; see
question 5.3, below.  There are also some national herp societies, like
the American Federation of Herpetoculturists in the United States, and a
number of global organizations with more specific purposes (like the
International Gecko Society and the Tortoise Trust).

Your local university library can also be very useful.  There's a
publication
called the _Zoological Record_ that indexes zoological journals by
species;
many of the articles it references will be unreadable by a lay audience,
but
others can be a very useful source of captive-care information.  In
addition,
university libraries can order copies of articles in hard-to-find
periodicals
for you; ask a reference librarian for sordid details.