yeah, it's freehanding anytime you don't have something that holds either the sharpener or blade at the edge angle for you. There's 3 combos-extra coarse/coarse, coarse/fine, and fine/extra fine
http://www.knivesplus.com/DMT-Knife-Sharpener-Dia-Sharp.HTML . The quickest cutter would be the extra coarse (best of the 3 to sharpen your tip), but then you wouldn't use that a lot and the coarse side would be the finest you have. The coarse/fine is a good combo, able to repair a little damage and thin a bevel with a little time, and the fine side will get you a decently smooth edge for regular use. The fine/extra fine will give you the smoothest finish, but it would be very slow in grinding out chips or thinning out thick edges.
You could get by with a file for the rough cutting on a 440A Leek, but it wouldn't do you much good on S30V or other steels with higher wear resistance. It depends on what you have now, and how much more sharpening stuff you plan to buy.
here's an abrasive grit chart, if you didn't see it in the other link
http://users.ameritech.net/knives/grits.htm
The specific types aren't too important right now, but it does show the general range of abrasives, and you can see the specific numbers for the diamonds on there. I have essentially 10 steps in micron size with my sharpening gear, from about 260 down to 1/2 a micron, and I have tried several different things.
Diamond is gonna be your fastest option, and it's also very easy to clean and use, needing only a little water.