I am doing the same as you, i.e. assembling my beginner's organ & worrying about the best way to start. I can offer you my experience with Perfumer's World's beginner's kit, I bought it a few years ago. While perhaps it was of some use to introducing olfactory training, I wasn't too thrilled with the kit. Some scents were *not very complex* - though this not entirely satisfactory experience may have been due to my utter lack of knowledge. From what I've read, they are a good supplier of small quantities of aroma chemicals, so I WILL keep them in mind when I enter into that daunting world whilst assembling my organ.
Also, I am keeping an eye to the future, as you are, and if I continue studying perfumery, I think you or I or any other beginner will be better off teaching ourselves with the actual materials we would work with rather than wasting money/olfactory training/time on 'study' materials.
If you wish, pm me, and we can compare notes on what each of us are doing as we seem to both be on the same step.