We will be staying in St. Martin for several days in September and are interested in restaurant suggestions and info about wine festivals. I am familiar with the Bad Durkheim Wurstfest, but have been unable to find info about smaller festivals. Thanks!
I don't know which link is "best" but here are a few places where you can search events over a range of dates:
http://www.mosellandtouristik.de/en/culture-events/wine-festivals/
http://www.romantic-germany.info/Wine-festivals.6114.0.html
http://www.germany.travel/en/index.html
http://www.travelsignposts.com/Germany/food/german-wine-and-beer-festivals
The German Wine Road isn't all that well known in the USA. I'm not sure whether Rick's newer GAS books even mention it, though perhaps they do refer to the Wurstmarkt. My GAS is pretty old. For the benefit of other readers, here's the area within the Palatinate that you will be in:
Here is a general informational guide for the Palatinate in English:
http://flyhahn.com/regions/pfalz-holiday-region-rhineland-palatinate-germany.htm
Here's a fest in Neustadt - probably not possible if you'll be in the Palatinate during the Wurstmarkt:
http://www.romantic-germany.info/things-to-do/leisure-tips/wine-festivals/events/2017-09-29/Deutsches-Weinlesefest_Neustadt-Weinstrasse/deskline-details.html
Without your specific dates, it's a bit of a goose chase. There are 30 September festivals listed by town for the Palatinate in the calendar/guide below; September begins on p.23:
https://issuu.com/suedlicheweinstrasse/docs/rz_bro_weinfestkalender_2017_freiga
We can hunt down some info on specific fests for you (probably in German) if you specify dates.