Not the very latest release but certainly still valid for many things.
Rolf Kersten from Sun wrote the “The 20% of Solaris knowledge that solves 80% of your needs” guide.
Here are 2 links where to get it.
1) Version 1.17e, 24. Jul. 2003
Solaris OE Guide for New System Administrators – The 20% of Solaris knowledge that solves 80% of your needs by Rolf Kersten