First thing is, do you know anyone with an M-Pesa account?
Yes I do. Whats next?
Great! First of all, if they have any concerns, PM me with their email and I'll be happy to address them.
The basic strategy is to have them setup a listing on LocalBitcoins.com listing Bitcoin to M-Pesa and Ksh available. They can set a quite low limit as to the amount of money they can spare for this and set whatever price they want since they're the first. The main competitor in Internet transfers is is PayPal, getting Ksh or M-Pesa from which will likely cost 30-50%.
Once they have a listing, I'll be happy to put them up on the front page of bitcoins.co.ke and it'll stay there until there are too many to list.
Personally, I would like to try making a purchase from Pewahewa.com (an online music store) and will pay bitcoins to the sender of the M-Pesa for a first transaction.