I think you need to decide what you are trying to make and what you want to do with it, there are at least three very different types of "crook knife". The ones posted by RB (very nice too) are examples od the East coast or woodlands Indian type sometimes called "Mocataugan" These were used more as a drawknife than anything else, original ones are not always crooked at all and often made out of old razors, they were used for all manner of work such as shaping the ribs of a birch bark canoe, or making a paddle, everything a European would use a drawknife and shavehorse for.
Like a drawknife they will function with bevel down or bevel up they will just work differently and take a little getting used to holding it at just the right angle to get it working for you, some I am sure are much sweeter than others but I would stick what you have made in a handle and give it a go, its the best possible way to learn.
The link cariboo posted is to making West Coast style crooks, a rather more refined tool that was used for carving poles, bowls and masks. They tend to have flat outside and bevel inside and be double edged so can be used pushing as well as pulling. Some makers also offer bevel outside options.
The Frosts is typical of the Scandinavian or European type hook knife which is generally used one handed and on the pull stroke like a potato peeler. They tend to have outside bevel and be used for hollowing spoons, kuksas and the like. There is a similar Welsh tool called a twca cam (hook knife) which is nearly always on a long handle and I have watched spooncarvers in Romania using an almost identical tool. There is a passaround of all the best of this type going on at the moment.
http://www.bushcraftuk.com/forum/showthread.php?t=29676
http://www.bushcraftuk.com/forum/showthread.php?t=29485
And if you want any more here is a video of me hollowing a spoon with one.
http://uk.youtube.com/watch?v=Y1TMhj9t2PY