Kurogane,
I have to stress, it is not as easy as it looks, or everybody would build their own laminated bows. I used Bingham supplies, and one of their plans for the first 3 bows. My first bow broke at full draw because of inexperience feathering the riser block. I then built 2 successful bows that had pretty mediocre performance. I did kill a young buck with the second bow. I built several more, building a couple molds. Then I worked with a friend and we built 2 more molds for take-down longbows. Again, we got mediocre performance. Finally we went with a pretty straight limbed recurve and got an average performing bow we could predict the weight on. I made a few of those, using the same mold to build both take-down and one-piece recurves. I even made a black widow knock-off. About then I saw an add for a John Strunk self bow class, which I attended. There I made mullberry and vine maple self bows. I haven't built a laminated glass bow since, though I enjoy shooting them. I still have a couple of the straight limbed longbows I built, including that second bow that took the buck. All the others are gone, given away, and I shoot Bear bows and a Samick if want to shoot glass. My bows just weren't that good in performance.
I say all that to say this. Coming up with a design, even if you copy an existing bow, is time consuming and expensive. Using a Bingham plan is a much better choice, but it won't look like the Tomahawk. I think they do have a reflex/deflex longbow plan though. Cutting and shaping fiberglass is hard on tools and can cause some health issues if you don't use a good dust mask. Unless it's going to be your hobby it may actually be cheaper in the long run to buy what you want.
If you make your own bow, take lots of pictures. I'd sure like to see how it turns out. Good luck.
George