Far the best, and most objective, history is Peter T.
Leeson's
"Better off
Stateless", which should be required reading for anyone
seeking to understand the history of Somalia over the past
half-century. The original is a PDF file, I'm
not sure the link works right, but try that if you'd rather.
It would be useful if you wish to download and preserve.
This is your suggested starting point
for understanding both Somalia and anarchy.