Here are two of my favourites, the All Back hair included in MayaX's pack has many variations as you can see and the Timeless hair works well for a clean, neat look.

http://www.renderosity.com/mod/bcs/3type-hair-for-men/85907

http://www.daz3d.com/timeless-male-hair

There's also this similar to the All-Back but without so many styles:   http://www.daz3d.com/royal-prince-hair

And then are many by Neftis:

http://www.daz3d.com/mature-mark-hair

http://www.daz3d.com/preppy-hairstyle

http://www.daz3d.com/uptown-boy-hairstyle

http://www.daz3d.com/cq-event-hairstyle