I found this interactive map online which may be of help.
However you have to remember that many outside influences have come into play with movement of population, incursions by outsiders, governmental decisions and climatic changes. The demands of an increasing population for food and water have changed the boundaries and will continue to do so.
The traditional tribal boundaries have all but disappeared as Kenyan citizens move from their ancestral homelands to the cities. Land issues and the rights to these have been a constant problem for many years.
I have noted that even in Nakuru [Rift Valley] there are tribal divides and I wonder how long this will go on. The city of Nairobi seems to more cosmopolitan but of course the issue of land and its title is set in concrete and steel.
Personally I would be happy to have a shamba which could sustain me and my extended family in Kenya. I have no problem with tribal conflicts and land issues and I pray earnestly that all Kenyans will make this work.
I could go on and on but I hope the map will be of use to you
Regards
Archie
http://memory.loc.gov/cgi-bin/map_item.pl
May 05, 2010
Tribal maps by: Arjen (webmaster)
The maps on this site cannot always be found through the search function, so I will paste some URLs here:
On this page, there's a map of the language groups in Kenya (from which you could deduce information about the tribes)...
http://www.kenya-advisor.com/kenya-map.html
And here, there's a map showing some of the main tribes in Kenya.