Go to whatever place sells Blade or Tactical knives; or google on knifemaking videos. Both magazines and the online markets offer advertisers who sell videos. Most of the major knifemaking supply houses(Jantz, Sheffield, Texas knifemakers supply etc) also stock them. Based on my own personal experience, I'd recommend starting with fairly simple kits that reflect the style of knife you're most interested in and working my way up until I understand a lot of the mechanics involved; and there are a lot of them.
Once your kit knives look good, then it's time to try making them from scratch. That's only one direction, there are others depending on what personal skills you may already possess.