Highly appreciate the tip! I will check these two out. I became interested after reading Dr. Paul Freedman's books on the era. Such a bloodthirsty time period in Western Civ. I bet a TV miniseries of this era would make "Game of Thrones" seem like "Alice in Wonderland".I haven't seen anything particular to the kings, but the two decent books on the period I've found are:
Before France and Germany: The Creation and Transformation of the Merovingian World
The Merovingian Kingdoms 450–751
I wouldn't consider either of them great, but they're what I know of.