I'm glad to see there are other knife enthusiasts/users on here.
I wouldn't reccommend buying a pocket knife for your primary self defense tool unless you are trained, but you want to see some wicked ones so here you go...
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cutleryshoppe.com and yourcornerstore.com generally have the lowest prices. also, bladeforums.com is a good place for more opinions. My favorite brand is Spyderco, but also check out Kershaw and Benchmade for sure and maybe others like Cold Steel or Kabar.
BTW my first knife was a Spyderco Delica Wave. It opens as you pull it from your pocket, so it's ready faster than any switchblade.