I typically use the Excel Elites or the Excel Elites with Satin Edges for quick detailing. If you want to go a little cheaper you can always go with the Blue Supremes. They have other color Supremes as well (grey and yellow).
Pakshak's MICROPAK 16" x 24" Ultra-Plush Micro Fiber Towel or MICROPAK 16" x 24" Ultra-Microband Plush Micro Fiber Towel. They work great and look really nice in a variety of colors.