1. A Metal Detector.
Without this, the rest of the list won't matter a whole lot.
2. A Loop Cover for your detector's coil (Maybe).
It looks like a Frisbee and snaps right onto your coil. This little device (usually costs about $7) is a bit controversial. Some treasure hunters love them and some don't.
Use one because it saves your expensive coil from all the wear and tear that you give it as you scrape it across the ground.
OR, Don't use one because it makes your detector a little heavier and it robs you of depth (the thickness of the cover moves your coil that fraction of an inch away from your target).
I personally prefer not using the cover.
3. Headphones.
If you are hunting in areas without much background noise, use a set of Walkman-type headphones. If there is a lot of noise around you (traffic, machinery, fast-flowing water), use a larger set of headphones with earcups that completely cover your ears.
I personally seldom use the big headphones because they make my head sweat, and they are particularly uncomfortable in hot weather. But deeper coins give a quieter beep, and you want to be sure you don't miss a good find because your headphones were drowned out by extraneous noise.
Headphones that are made for indoor stereo listening are often too fragile to stand up well in the field. Get a pair of headphones especially made for metal detecting. Plan to spend about $40 to $100. I like the Audiophone II.
4. A Hunting Knife.
I've tried several different methods of digging up the coins my detector finds, and for me a hunting knife is the way to go. I cut a "V" shape in the ground around the coin, about the size of a piece of pie, then I carefully lift the plug without tearing it loose from the ground. (The uncut side of the triangle serves as a hinge). I retrieve the coin, carefully replace the dirt plug, stomp it back into place, and move on. If you are doing this right, nobody will be able to tell you dug a hole.
The knife's blade should be thick enough not to bend, but thin enough to dig easily into the ground. And the knife should have a rounded handle-top, so when you push the knife into the ground you don't rub calluses into your palm (I learned the hard way).
5. A pinpointer.
This wonderful gizmo looks like a walkie-talkie. The tip is a tiny metal detector that beeps when it gets within a half-inch or so of metal.
Here's how I use it: When I get a beep from my main detector, I first run the tip of the pinpointer over the ground where I got the beep. If it beeps, I know the coin is right near the surface, and I pop it up with a screwdriver.
If I don't get a beep, I dig my "V"-shaped plug, as explained above. I run the tip of the pinpointer over the plug and the edges of the hole, and it shows me exactly where the coin is. If I don't get a beep, I know the coin must be deeper so I enlarge the hole and repeat the maneuver.
By my estimation, the pinpointer cuts in half the time required to dig a coin. Which means my actual hunting time is doubled. This tool is like a TV remote control or a cordless phone: You don't realize how much you need it until you actually use it. I use the inexpensive Harbor Freight pinpointer pictured above.
Here's a video of me digging a coin, using this pinpointer.
6. An electrician's screwdriver with a blunted end.
Use it to pop up those shallow coins, and to carefully extract coins from the edges of holes (the pinpointer locates these, and the screwdriver retrieves them). Use a file or grindstone to smoothly round the end of the screwdriver so you are less likely to scratch coins as you probe for them.
7. A nail apron.
Put your good finds in one pocket, junk in the other. When you go by a trash can, empty your junk pocket. When I'm hunting in a schoolyard or park, I like to pick up some pieces of pop cans that have been hit by lawnmowers, and keep them in my junk pocket. These are ugly-looking things, with sharp jagged edges. If anyone ever approaches me to angrily tell me to leave (hasn't happened to me, but has to some of my customers), I can show them the sharp metal pieces and say, "Look what I'm picking up. Would you want your kid to fall on this?" That should confirm your usefulness.
8. Two books: The Metal Detecting Manual (which I wrote), and Charles Garrett's book on finding coins.
I've seen dozens of books for metal detector hobbyists, and these are the best of the lot. I highly recommend that newbies and experienced hobbyists alike read these two books from cover to cover. They contain a treasure trove of hints, tips, ideas, and explanations of how and where to treasure hunt. Charlie's book is the most in-depth study of finding coins ever written, and my book covers just about everything you'll encounter in metal detecting and treasure hunting.
If you get discouraged because you aren't finding much, these books will recharge your batteries.
One more book that isn't about treasure hunting, but nice to have in the field: The Boy Scout Handbook. Full of essential information for the outdoorsman. Many people prefer older editions of the book to the new one, because the older ones have more information about living in the wild.
Put It All Together...
I'm right-handed, so I carry my detector in my right hand. In my left hand is my digging knife, my screwdriver, and my pinpointer. When I get a beep, I drop to my knees and run the pinpointer over the ground. I dig with the knife or the screwdriver (depending on how deep the coin is), retrieve the coin and put it in my nail apron, and then I stand up to swing my detector for the next coin.
That's It--Let's Go Detecting!
I do want to emphasize that the accessories listed above are the ones I use myself. Everybody has his/her own style, and when you get some experience you will undoubtedly do things differently than I do. But I think my way is a good, solid way to start out on the right foot.
And I didn't list things that you should consider carrying even though they aren't directly related to treasure hunting. Things like sunscreen lotion and a first aid kit. Some people carry a gun (rattlesnakes and human snakes). Back to the Boy Scouts: Be Prepared!
Oh, before I forget--carry extra batteries for your detector! Nothing more maddening that having your batteries go dead in the field and you're miles from a store.
Questions? Comments? Just wanna talk metal detecting? Buzz me anytime!