Cook the beef in large skillet over medium-high heat until browned, stirring to crumble. Stir in taco seasoning and water. Reduce heat, and simmer 5 minutes, stirring occasionally.
Combine sour cream and salsa in a small bowl.
Combine the beef mixture, iceberg lettuce, tortilla chips, tomatoes, 1/2 cup cheese, and beans in a large bowl.
Drizzle the sour cream mixture over the salad, and toss gently.