In a large bowl, mix all burger ingredients with your hands. Form the mixture into 4 patties. Heat the burners on your gas grill to medium high flames. Once hot ( after about 10 minutes), grill the patties for 5-7 minutes per side.
In a large bowl, mix all tomato salsa ingredients. Cover and let sit while you make the burgers (refrigerate if it will be sitting for longer than 1 hour).
In a medium bowl, mix all yogurt sauce ingredients. Cover and refrigerate until ready to serve.
Assemble burgers on lettuce wraps or buns. Spread yogurt sauce on lamb burgers and top with tomato salsa. Serve.