Begin by becoming very familiar with the metal detecting code.
Then, as you've probably read, the best place to find coins is where people have been. This takes a little research. First, though, you don't have to drive hundreds of miles. Staying close to home puts more fun in, and takes the pain of gas out.
Start your research at your local library and historical society or history museum. Starting with whenever your area was settled (1:loveit:X) to say 1965,
find as many places as you can where people gathered, played, had fun, and generally raised hell. Old maps, pictures and newspapers are particularly good sources for this kind of info.
With those location in mind what is the least detector I need for silver and well, anything of higher value... You've, also, likely noticed in the discussions that low frequencies work best for highly conductive metals like silver, and higher frequencies work best for less conductive metals like gold. It figures, you can't have it both ways unless you go to a multi-frequency detector, which means big bucks.
So, what is a detectorist to do? You have a number of options. Based on your research, what are you most likely to find? Probably silver coins and jewelry. Nuts! Another frequency dilemma. Do they ever end?
Sure...but you have to make some hard choices. If your game is truly silver, and it's really too early in the career to tell, a low frequency (3kHz or so) detector is your weapon of choice. Forget about other forms of treasure. You'll find some, but not as much as you might.
Ahh...gold and silver jewelry. A treasure hunters dream...sometimes, if you don't get caught up by other areas of the hobby. To maximize these finds, you want a higher frequency (say 15kHz). Silver? Oh, you'll find some but not near as much as you might. Sound familiar?
But you want it all! And coming into the hobby, all hasn't even begun to define it's self for you. Try this as a workable alternative. Take the 3kHz for silver, mix with the 15 kHz for gold and jewelry, mix well and come up with around 7kHz (plus of minus a few tenths). Perfect? No. It's a real good blend and seems to do well for many. Now, all you have to do is study the literature/web sites for the major brands, and make a choice.
Wrong. As important as frequency seems to be, ground balance is equally important or more important. In your initial price range, you will not find auto adjusting ground balance. It's a fancy toy for the expensive boys. You will find manual ground balance on a number of machines close to your range. Seek them out.
And, don't forget, you can easily spend hundreds in additions such as head phones ($30-150), digging knife (trowel) ($30-40[don't go cheap] , pin pointer (don't go cheap there, either. Garrett is probably the best hand held [$120-140]), carry case, etc.
GL & HH