If the sources are correct the roots of M-min category (at least in Czech Republic, former Czechoslovakia) are in the middle of sixties. The golden period was in the seventies with several competitions per year with dozens of models on each contest. The rules changed and evolved into its final form, which is valid for last 20 years. In principle the rules are simple:
Zlin XII by Robert Pajas - new model on Openscale 2007
Full version of rules on this server (unofficial translation) is on this server [ here ]. The beauty of of M-min, which can be due to its size made in more detail than peanuts (there are exceptions), small material requirements for both building and flying, all this together seems to be "sexy" enough even at this time, so the modellers meet at least twice a year in Brno Medlánky. May Openscale 2007 proved that M-min category is still alive, new beautiful models appeared (Zlin XII by Robert Pajas, perfectly made MC-202 by Petr Kolář, and others).
The risk of M-min is the outdoor flying, mainly together with competitive nature of models owner. There are several traps: from windy turbulent weather, which can knock down the model very fast (remember that flight weight is in range of 30-80g) to thermical weather, which can take model to unknown place (models are not equipped with determalizer). Well, that's the M-min.
At first try this server 
,
but that is not the only source.
Koutný: Modely letadel s
gumovým pohonem
There is still available book by L.Koutný entitled "Modely letadel s gumovým pohonem" (Airplane models powered by rubber band), (ISBN 80-251-0042-1). The book is available in Czech only, and author writes also about non-scale models, but there are plans included, for models which are well known, but models beautiful and very good fliers (Musketeer, Arsenal VG-39,..). And that might be nice inspiration even if you don't understand the language. At this moment (June 30, 2007), the publisher web shop shows the book on sale, prize being 21 Czech crowns ( 1.00 $ - yes, one single dollar), see here.
Some information can be found in Czech "Model Hobby" magazine, however be careful before ordering
it, some issues are completely useless for scale free flight modeller (and even for other kinds
).
On the internet pages of the magazine several plans can be found under the
"Volné minimakety" (free flight scale models)
section. At least Ki-84 "Frank" is a great flier and Partenavia P-66 Oskar can be built and flown
by beginner.
