welcome Paul, from what I have learned so far from the forum I would stop collecting parts until you have a solid design worked out. From reading the answers from some of the experts this can save you a lot of money in the long run basically because you have unknowingly bought parts that are not really suitable for the machine your building.
I would start by reading through some of the build logs & then start a post of your own about the design, you will need to let people know what you want the machine to do, what sort of size machine your looking to build & the type of materials you want to be able to cut.