One of my favorite authors/speakers is C.J. Mahaney.  He is a man consumed with a passion for the cross and humility.  C.J. Mahaney oversees the Sovereign Grace Ministries.  He has written several books, most notably "The Cross-Centered Life" and "Humility".  In a recent post he discusses how to address the symptoms of spiritual dehydration.  Check out what C.J. has to say at his blog.