Whats the best gauge and where to get it. Think Ill wrap my backup knife handle with snare wire then paracord.

what are you trying to snare? rabbits/people/bears/armored personnel carriers?
 

ebay

Stainless steel safety wire (for aeronautics) is good.

Yeah, you need to define what size game you plan on snaring.  For anything under 50 pounds (beaver, rabbit, squirrel, etc.), I like simple 24 gauge brass wire.  It's easier to bend and can also be used for repairs.

Even with 30 to 40 feet of brass wire, I still have pre-made snares with a few sizes for large game like deer (the smaller SE deer).  I'm fortunate enough (when home and not deployed) to have access with plenty of property around our lake where I've been experimenting with snaring.  I've got a decent population of squirrels and rabbits and when the cursed beavers show up.  There are tons of game trails to the lake's edge so it takes time to scout and figure out which are the most active.  

ROCK6

Yeah, as Soowah also mentioned and motivated me to find some pictures of a couple of my kits.  Conibear traps are the most effective I've used; although much heavier than snares, as long as you can located an active trail or burrow, you're guaranteed  that if a critter passes through, you will have dinner (or breakfast).  

I don't have conibears in my smaller 3-day pack, but I do have a larger bag that is dedicated to snaring, trapping, fishing, gigging and gill-netting.

Smaller kit tossed in the backpack:




Larger kit, more geared for an INCH scenario:





ROCK6

You got a website or a good book to show someone like me what to do with all that stuff?  I really don't what to get something like that and end up just throwing a big stick at a rabbit.

I just use snares of different sizes depending on the game I'm going after.  You can carry dozens of snares for the weight of ONE trap.  In a SHTF scenario, the last thing I'm going to carry is a large conibear trap/body gripper.  If you ever get caught in one you stand a good chance of severely bruising your arm/wrist/hand, if not breaking it.  That's among the last things I'd take a chance on.  Another trapper I know has done it on his beaver line.  And then there's always the problem of releasing yourself one handed.  I use them on my "normal" trap line, but I won't if it's SHTF.

You can pick up snares and snaring books/videos at Minnesota Trapline, The Snare Shop, and other places.

For a great trapping forum to learn techniques try Trapperman.  Remember, it's all about fur snaring/trapping now.  It's illegal to snare game animals.  In a SHTF scenario everyone will have to make their own decisions.

What are the little reel/spool looking things and where did you get them? Im guessing maybe fishing reels of some sort.
Also I have seen where you can carry a couple large rat traps they are light weight and suppose to work well on small game. No personal experience.

XSabers is correct about the weight of the conibear traps verse number of snares you can pack: however my success rate with conibears is much greater than snares.  They both require good placement near active burrows or trails, but a little peanut butter or fish on the conibear will guarnetee me a catch if there are any inquisitive critters in the area.  Unfortunately, I don't pack them in my regular bug out bag or E&E kits; I do have the dedicated trapper's bag to grab if heading out though.



They're the simple "Yo-Yo" reels.  They can be used for fishing and even squirrels or birds.  You set up your bait/hook, attach to your anchor or trot line, unwind, set the trigger and that's it.  They work really well on bream I have in my lake and although I've heard their also good for catfish, I haven't had any luck.  I've tried them on squirrels and just never had any luck, but I've seen them work.

ROCK6