Not sure where you live but if you have any travel agency that specialize in Adventure Travel in your area they can be of great help.

We used the Adventure Centre in Toronto a few years ago for a safari to Kenya and again for a trip to the Gallapagos and they were great. They do have a web site: Adventure Centre

I have never tried the Kili climb but I have heard a lot of negative comments over the years. A good agent should be able to provide you with both sides of the story.