Which type of airfoil does the 737 use?
Boeing designs its own airfoils for its aricraft. According to this site, the following airfoils are used in 737:

Boeing 737-100: Wing root- BAC 449/450/451; Wing tip- BAC 442

Boeing 737-200: Wing root- BAC 449/450/451; Wing tip- BAC 442

Boeing 737-300: Wing root- BAC 449/450/451; Wing tip- BAC 442 mod

Boeing 737-400: Wing root- BAC 449/450/451; Wing tip- BAC 442 mod

Boeing 737-500: Wing root- BAC 449/450/451; Wing tip- BAC 442 mod

The 737 wings are manufactured at the Boeing plant in Renton, Washington.