Collecting second hand books can be a satisfying and rewarding hobby.  Here are some thoughts that will help you get started. 

1. First establish your motives

Books can be bought for reading, reference and collecting. 

• Paperback reading copies can be obtained extremely cheaply but carry negligible resale value.
• Expect to obtain bargains when purchasing reference material. Technical books are niche and are of more value to a specialist than a second hand dealer.  Once again, do not expect more than marginal resale value.                                              
• Collections can be built up for their own pleasure and as a financial asset. When collecting, the condition of the book is paramount.

2. Focus your collection in specific areas

There are a very wide range of ways in which you could organise your collection.  An obvious choice would be to collect by author, or subject or genre. However there are any other alternatives. The collection could focus upon the winners of a particular prize, such as the Orange prize for fiction, or even specialise in all published editions of a particular book. Some collectors specialise in the works of a particular illustrator, or publisher, or collect on the basis of dust cover designs. Others collect first editions. Some try to collect advance review copies or galley proofs. as in stamp collecting, it is possible to collect a particular thematic.

A set of books on a particular theme is unlikely to carry significant premium over the value of the individual books themselves.

The focus is relevant for other reasons.

• It directs research. The book buyer needs to be able to identify collectors items that have been overlooked in the flea market and car boot sale.
• It helps prevent sentiment and impulse getting in the way of the book buying process.  These emotions seldom lead to good business decisions.
• It gives confidence that you know your slot. 
• From this knowledge you will be able to converse with fellow book enthusiasts.

3. Research your niche.

Once you have established your niche research the market.  Try to establish a shortlist of the books that you are looking for.  This could be straightforward if seeking a collection by a particular author, or a collection of winners of a particular literary prize.  It is a much harder task of you are seeking books on a particular topic.  Start by compiling a bibliography from exisiting books on a topic and ask your local library for help.

Once the shortlist is established it may be possible to obtain the book using the internet, or at least obtain a valuation.  From my experience prices quoted on the internet can vary between wholesalers and the interpretations of book condition (Excellent, Very Good, Good and Fair) can be open to interpretation. Generally the trade tries to describe the book in the best possible light. Very good will refer to a well presented book that has been read, possibly showing crease marks on the spine and soforth.  Fair will refer to a well worn book.  

The collectability of a book will depend upon its rarity, condition and interest. All else being equal, if a story attaches to the book, it should add value.  For example, a 1960’s edition of the Penguin paperback Lady Chatterley’s Lover might be more valuable than another 1960’s Pengiun because of the noteriety of the court case which lead to the relaxation of censorship rules in the United Kingdom.  Prevenance is useful if the book has been in the possession of a famous person.  Signed copies are generally not significant on modern books, book signing has become part of a modern publishing deal but may be significant on an older book.

4. Search the market

This is the fun part.  Be prepared to be patient.

In our times, if money is no object, it is possible to complete much of a collection very quickly using the internet.  This frees the collector to specialise in hunting down the more difficult titles. Some collectors quickly build up a basic collection then replace with better quality books as they become available.

Alternatively, the collector could build up a collection more slowly with modest means by attending car boot sales, fetes and junk shops.

Search out your titles in all of the following places.

• Online Wholesalers (Book Barns)
• Online Private Collectors
• At book fairs
• At car boot sales and flea markets
• In second hand bookshops and in junk shops
• In charity bookshops
• At fairs and charity events

5. Remember when you make a purchase that the condition of the book is very important for long term collectibility.

Pay attention to the storage of your books.  Books should be kept in dry conditions away from direct sunlight. It is a good idea to browse them periodically to prevent the build up of book mites.

These thoughts should form the basis of a satisfying and rewarding hobby.