Truffles@ Richerenches in the Vaucluse
As far as I know this is the most established truffle market in Touraine. Truffles are a growing business in the Loire with more and more truffle oak being planted. The first market in the 2010-2011 season will be on Tuesday 21st December (the shortest day in year). After that there is a market on Tuesday 28th January. Then the second and fourth Saturday of January with the last one on the second Saturday of February.
'Marché aux truffes - 21 et 28 décembre - 2ème et 4éme samedi de janvier - 2éme samedi de février. De 8h00 à 13h30 - Salle Polyvalente'
Further details here – although there is a disagreement about start time.