LOTS and LOTS of videos and blogs out there, both in forums such as here and YouTube. Like to hear the thoughts of others here, and feel free to "school" me gently if you wish... I sure don't know every dang thing and am ready to learn more from my betters in this arena. Here's some of my thoughts (and actual choices made) on the subject: A) Budget is a big concern for many obviously. B) Practicality i.e. effectiveness C) Ammo availability. First off, my comments on the Glock pistol of choice, because there are so many arguments for the 19 & 17 in 9mm, the 22 and 23 in .40, and so on. I maintain that the only choices of these four is the 22&23 Because: if you purchase a 22 (my favorite) you can also purchase a SECOND BARREL which will allow you to shoot either 9mm or .40 from the very same gun. This can be vital if and when ammo becomes scarce, and looking for TWO available calibers sure beats being limited to ONE. Matching up Carbine & pistols can be a practical idea as well. I, for example, have a .357 lever carbine coupled with a .357 revolver. I can not only utilize and carry the same ammo for both, but again can have a choice between using .357 or .38 special. There is a better chance of obtaining ammo from those two choices when it becomes rare. Ditto of course for the .44 carbine and revolver, although I prefer the .357/.38 due to the monster amount of .38 revolvers made over the last century... and I feel there will be MUCH more .38 around than .44. One can match up a Kel Tec Sub 2000 with that Glock, utilizing the same ammo AND Glock clips. You WILL have to choose between 9mm and .40... I went with the 9mm because I think there is going to be more of that caliber around for longer. There are TONS of super cool rifles and pistols out there which I never consider. Do I like 10mm for example? Yes, a very cool caliber... but I just don't imagine being able to find any after my supply runs out. Ditto calibers like .44 special, .50AE, or .22 WMR. I either stick to the common NATO rounds, or stuff you are likely to find in every other grandpa's drawer like the .30-.30. And yes, I have an AR (also a NATO round) which is my first choice. These are ideas for other interesting and practical COMBOS when ammo is hard to come by. Anyone got any favs?