Check out:

http://www.alaskaair.com/content/tra...-aircraft.aspx

You can find seat maps for all the planes there, and there may be different configurations for each plane type.

There are missing row numbers to ensure that some rows are the same between all 737 plane types. Row 6 is always the first row in coach, row 15 is always the non-reclining row before the exit rows, and rows 16-17 are always the exit rows.