Check out bladeforums.com
They're going to have some really knowledgable guys, and some great ideas/recommendations about what's best for everyday carry (EDC). Theres crazy arguments on blade steels, etc (very much like our "synthetic vs dino" threads here...those dudes have far more experience than I can give you.
Depending on where you are in Missouri, Bass Pro Shops in Springfield has a great selection of knives from $10 to $500
When I was in the Army my favorite pocket knives were a Benchmade Griptilian ($80), a Spyderco Native ($50), and a Spyderco Military ($125), which are a little more on the expensive side.
also the Spyderco Delica and Endura were decent knives but they're targeting more of a different market.
Regarding brands most common used in the army....Gerber, Benchmade, CRKT, SOG, Spyderco, Boker, and KaBar seemed to be the most knives used. Of course saying which is best is like arguing Ford vs Chevy vs Dodge and resulted on more than one altercation in my unit.
I'm rather biased toward Spyderco because when I was deployed to Iraq, one of the Spyderco forum members organized some Spyderco collectors and they began sending us knives as gifts...which were greatly appreciated. (In fact, the Spyderco Native thats one of my fav's was an AWESOME gift)...give Kudos to the Spyderco guys
Right now I carry either the Spyderco Native or the Benchmade Griptilian. (Had both about 6 years now). Clips are still in great shape and they don't slip out of my pocket.
hope I've helped.
Joe