You could read the paper on the CSJ website:
http://www.csj.org.uk/route-swiss.htm
Guide books.
* Les Chemins de Saint-Jacques à travers la Suisse, by Jolanda Blum, Ott Verlag + Druck AG: Thun, 1999. This is a direct translation of the original German version, published in 1998. Both guides provide detailed historical information and route descriptions but nothing on accommodation or other services.
* Wandern auf dem Jakobsweg, by Peter Witschi, Appenzeller Verlag-Herisau, 1998. Route description, very good (Ordinance Survey type) maps, historical information.
* Unterwegssein auf dem Jakobsweg, vom Bodensee zum Genfersee durchs Berner Oberland is a very useful (free) 128 page booklet (even if you can't read German very well) and is widely available in Tourist Offices, church bookstalls etc. It gives timings from place to place, historical information and many small photos helpful in recognising places of interest and also includes small sketch plans. This covers the route from Konstanz. A parallel booklet, Von Rorschach nach Romont durchs Berner Oberland deals with the St. Gallen branch.
* A CSJ guide (route description, accommodation and services, what to see) is in preparation.
* The Swiss Association now publishes a set of A4-size colour maps of the route. Enquiries to the address of the French-language branch (below).
Mapping. Peter Robins reports [October 2007]: "... detailed online mapping of the Swiss route(s) is available on the IVS' excellent GIS site
http://ivs-gis.admin.ch/ - high quality, as ever with CH."