As promised earlier, here's a list of books I would recommend to those interested in the Freikorps Werdenfels, the situation in Munich and Germany in 1918/1919 and (limited) also the Freikorps in general. A downside with most of the books is certainly that most are out of print and also only available in German language. I'm sorry for that.
If you've got additional recommendations please let me know!
General information on the Freikorps
The German Freikorps 1918-23 (English) by Carlos Caballero Jurado (Osprey Publishing)
Like most books by Osprey this gives a solid overview for a decent price. If you think about starting an Freikorps project or are just generally interested, this would be a good starting point.
German Uniforms, Insignia & Equipment 1918-1923 - Freikorps - Reichswehr - Vehicles - Weapons (English) by Charles Woolley (Schiffer Military History)
(Sligtly bigger than A4, hardcover, about 180 pages.) As the title suggests a lot of contemporary photos and plates focusing on uniforms & equipment. Also some brief texts and explanations.
Information on Munich
Fotografie und Revolution - München 1918/19 (German) by Rudolf Herz and Dirk Halfbrodt (Verlag Dirk Nishen & the Münchner Stadtmuseum)
(Sligtly bigger than A4, hardcover, about 320 pages.) Published on the occasion of an exhibition at the Münchner Stadtmuseum - Munich City Museum in 1988.
A great resource for photos of Munich in 1918/19 but it also has quite a lot of interesting text about the different stages of the revolution and counterrevolution and how photographs were used for propaganda. It also shows how certain photos were retouched to give a different impression for the audience. There's also a very interesting chapter on how the Nazi propaganda used the events in Munich massivly to support their rise to power.
(Heinrich Hoffmann, one of the main photographers in Munich during this time became a NSDAP member very early on and also some kind of private photographer of Adolf Hitler.)
There's also a volume dealing with the situation in Berlin available but as I don't own it, I can't comment on that one.
Die Münchener Räterepublik - Portraits einer Revolution (German) by Michaela Karl (Patmos Verlag)
(About A5, hardcover, about 250 pages.) Very interesting book on the background of many leading personalities of the revolution and the council republic. It also gives a rather fair and objective, imho, insight on the struggles they had to face.
Information on the Freikorps Werdenfels
Revolutionszeit im Bezirk Garmisch 1918/19 (German) by Josef Ostler (Mohr - Löwe - Raute)
(About A5, softcover, about 170 pages.) THE source on the Freikrops Werdenfels. It has nearly all available information gathered in a single volume. A lot of photos, detailed enlistment information, reports, etc. It also deals with the situation in the county of Garmisch during the Great War and the revolution in Munich/Bavaria. Furthermore it has a detailed account about the Garmischer Volkswehr - militia (the predecessor of the Freikorps Werdenfels) and a fire fight it participated in.