A very nice isfdb bibliography with a more complete listing of Harry's articles is available at
http://www.isfdb.org/cgi-bin/ea.cgi?892
None of the listings above include any info on foreign editions of Harry Stine's books.
Here is what I know of foreign editions of Harry's books:
Foreign Translations of Handbook of Model Rocketry:
Missili Con Propulsione A Razzo
(Italian translation of The Handbook of Model Rocketry - 2nd Edition)
Translation by Guido Antolini
U. Mursia & C.
Milan, Italy
1969
Cloth
I know the book did not have subsequent editions but I don't know if there were paperback editions.
Some of this book has actually been put online. You can read it, in the original Italian,
here.
Livre - Le Livre De Référence De L'Astromodéliste
(French edition of The Handbook of Model Rocketry, most likely the 6th edition since the cover picture is the same)
January 1996
Translation by Jean-Pierre Seingier
Editeur : Tradu-concept Genre : Fusées ( aéronautique) Langue : français EAN13 : 9782951024403
Bill Stine told me there was a privately published (with permission) Japanese version which was not sold to the general public. As far as Bill knew only roughly 500 copies were published. I have never been able to find any reference to this version anywhere.
Translation of "The New Model Rocketry Manual" from 1975.
Handbuch des Raketenmodellbaus (Taschenbuch)
ISBN# 0-668-04030-0
ESE Electronronics and Scientific Equipment
Hasenmoor, W. Germany 1977
Paperback