Das Ist Lustig can be found on Thursdays at The Sauer Kraut Grill in Richmond, Texas.  Check their calendar for a complete listing of dates.
Look for them to appear from time to time:
Sengelmann Hall in Schulenburg
Krause's Cafe in New Braunfels

When they go on tour out of town, they look for restaurants along the way where they can drop in and play a show or two.  They've entertained at Hollerbach's Willow Tree Cafe in Sanford Florida, Turek's Tavern in Choctaw, OK (now closed), Siegi's Restaurant in Tulsa, OK, The KC Bier Company in Kansas City, MO,   the Bavarian Bierhaus in Nashville, TN, the Hofbrau Beer Garden in Panama City Beach, Florida (now closed), Pecan Grove Store in Fredericksburg, TX, Walburg German Restaurant in Walburg, TX, Bavarian Grill in Plano, TX, Henk's European Deli in Dallas, TX, and the Old Stein Inn in Edgewater MD.  The food and service at each of these locations was excellent and most likely still is.  German beer and gemutlichkeit are always flowing.