I actually purchased TONS of ribbon straight out of the gate thinking I was in for a bow biz only to find that I do not like to mass produce anything. (So boring for my designing mind!!) I think that you need to get your techniques down, figure out what you love and go from there. Don't jump in to every group buy and don't buy tons of anything until you know that you will use it. (On the plus side, I now have a massive ribbon stash for when I am designing that frequently comes in handy.
Focus on quality, AMAZING photos, networking and make sure that you LOVE what you are doing or it will not be a successful business.
Also, I just had to add that not all tutorials are crap.