DiGi, if you don't mind my asking, where are you located?
My first succesful bows were D shaped. For me, I found them easier to tiller.
My two cents is - jump into it but take your time. I broke many when I first started and still do here and there. Figure out where you can make a pulley system. Take a pine 2x4 and make a tillering stick that you can clamp into a vice, step back, and take a picture of your progress. If you can, use a camera to look at the progress you make. I don't know why, but it makes it easier to see the ellipse of the bow when on the computer. If you don't have a digital camera, maybe you can use a cell phone or something. Microsoft Paint has a way to open up the pictures and draw an ellipse to show your progress. Many people on here know how to do this, so just ask.
Read about heat treating and see if you can find a heat gun. They make a big difference in the performance of 'white wood'. There are other ways to do this instead of a heat gun, but they are easiest. Make a string jig and order some B-50 Dacron to start. It's worth it, for sure.
Didn't see your draw length, but go long when starting. The dimensions given earlier look like good recommendations. Have fun and post pictures if you can.
You'll get a lot of really good feedback.