The plain fact about Reply Coupons is that most of them are, let's face it, plain.  They do not sport fancy engraving, fabulous color combinations, or even (for the most part) a wide range of denominations.  Why then, as my wife often asks, collect them?

     The answer, to me at least, is the challenge of fending off the almost palpable derision of most dealers who don't have time for philatelic items which are not stamps by finding the all too occasional new item for my collection.  Those of us who make the effort are rewarded just often enough to justify the frustration which is the usual result of walking a show's floor to a chorus of "No, I don't have any".  ( It does help, of course, to have a few other interests to track:  I also collect Postal Money Orders and I deal in U.S. bank checks and foreign paper money. )

      For those intrepid enough (silly enough?) to consider starting a collection while there still is a ground floor to get in on, the easy way to start is by collecting International Reply Coupons from the following countries; countries which are generally inexpensive and offer a lot of varieties:

U.S.A.
Great Britain
France
Germany
Israel

Second Tier countries could be

the rest of Western Europe (although the Baltic States are tough)
Argentina
Japan
Australia

    Having decided to get your feet wet, the best way to acquire Reply Coupons outside of the show circuits is by auction.  There are two semi-annual+ specialized auctions at present.  The older is conducted out of Bremen, Germany by my long-time friend Juergen Debus.   This is a rich field for better Coupons as well as the more common and more recent.  Country names are given in French (just as they are on the individual coupons themselves) and a smattering of German would be useful.  The pricing is in Euros.  Juergen reads and writes good English.  There is an annual membership fee which includes News Letters (in German).
His adddress is Juergen Debus
                        Lahnstrasse 82
                        28199 BREMEN        Germany.

     The second source of auctions is out of Bala Cynwyd, PA.  As of this posting, the next (September 2009) list will include over 200 coupons of varying rarity (minimum bids from $2.50 and up).  This and future lists may be requested from Peter Robin
                                                    Box 353
                                                    Bala Cynwyd, PA  19004.

     Available from this source are the following Guides to the field.

"International Reply Coupons --- An Illustrated Guide to their Types"    $ 15.00 + shipping
"An Illustrated Guide to Imperial and Commonwealth Reply Coupons"  $ 15.00 + shipping.
     Further information and sample pages on request.