How do you get Dungeons and Dragons first edition?
The most likely places to find copies are eBay and used book
stores. A few game stores, including some online retailers like
Noble Knight Games, also sell out-of-print role-playing games.
A lot of out-of-print D&D products were available for
purchase in PDF form online until Wizards of the Coast decided to
abruptly pull all PDF sales after catching a group of pirates
distributing a newly-released Dungeons & Dragons 4th edition
book. It is no longer possible to legally give the copyright
holders any money for old D&D products.
It's important to know what you want. There are three different
games that could arguably be called "Dungeons and Dragons 1st
edition": Advanced Dungeons & Dragons (AD&D) 1st edition
(consisting of a large number of books and boxed sets published
between 1977 and 1989), the original Dungeons & Dragons Basic
Rules (a rule book and a boxed set including the rule book, both
published in 1977) and the original Dungeons & Dragons game (a
box with three rulebooks published in 1974), sometimes called the
"Dungeons & Dragons Collectors Edition." AD&D material is
widely available. The original Basic Rules are harder to come by.
Original D&D rules sets are easy to find on eBay but usually go
for somewhere over $500.