well, first what are you going to be sharpening?
you cant go wrong with the diamond stones for most metals, specificially the powdered metals and high carbide stuff. but if you have budget steel you can get some cheaper stones.
otherwise id recomend the kit, Gold Series Coarse, Fine, X-Fine 3-Hone Set.. on top of that id get the beast 50 grit, 100 and 140. if you want to save just the 50 and 140. also never apex on the 50grit, apex on the 140 grit... as you will be just pulling out the carbides and never get it sharp as it could be. the 50 grit is great at removing material tho.
then id recommend the films and strops (your own bench strop or the kme strop, doesnt really matter).
some people and knives prefer other materials... there are many other choices at gritomatic who is a paid dealer here.