The Mid Life Crisis forum has a ton of helpful resources. The people there are experiencing it all first hand and can help. The following post should be helpful:

http://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=1539436#Post1539436

This thread has enough resources to keep you reading for awhile.

Me 45
M 25 yrs; T 31 yrs;bomb 8/15/06; moves out 7/18/08
D 18, D 14, S 12