Depends on what type you want -- junk silver, ASEs, Mint products, bars/ingots, or rounds. Keep in mind that every time you send off for silver, you are getting thoroughly whacked for postage, whether you pay up front, or the cost's hidden in the price. I live in Columbus, Ohio, a major metro area of almost two million people, so there's plenty of silver in ads, in CraigsList, in coin shows and flea markets, etc. I have never once sent off for silver, have always bought face-to-face -- no postage, and a good hard look before I commit.
As Doug mentioned, we need to know a little bit more about what you want. i.e. What form (coins, rounds, bars, etc), how much (1 oz, 10 oz, 100 oz, etc), any preferences or limitations (would rather buy in person, need it now, don't mind waiting for shipping, etc). There really are a lot of choices today. Local coin store, online bullion dealers, craigslist, ebay, coin shows, etc. Each has its own set of advantages and disadvantages, but each is the right choice for someone.
I didn't put how I want it because I welcome advice on that too. Are bars better value because they're not pretty? What are Ace's? It's no use using acronyms with me, because I'm not in the know.
If you want silver PURELY for protection from inflation, then you buy "junk silver," pre-1965 dimes, quarters, and half dollars in circulated condition, where you get the most bang for the buck. If you're more of a coin collector, then you buy silver eagles and various silver Mint products (but expect to pay a significant premium over current price per ounce). If you want flashy silver, buy rounds and bars, but keep in mind that somewhere down the line, you may have to convince a skeptical buyer that they are really silver, especially the mints and designs no one's ever heard of. If you need money fast, that may be a problem. Because I keep silver separate (both mentally and physically) from my coin collection, my holdings are 90% junk silver and 10% eagles. No high-priced slabbed Mint products for me, and absolutely no bars or rounds. You may wish to do something different. If things really come to a crunch in 3 to 5 years, a slabbed PF-70 Mint product that cost $$$ will sell for melt, just like junk silver, in my opinion.
A bit more commentary. Some people believe that over the coming years, silver will go up, percentage-wise, faster than gold; I happen to be one of them. Silver is more useful in commerce; who's going to make "change" for a gold eagle?? Right now, a silver dime (about $1.60) easily buys a loaf of bread; if hyperinflation comes, and bread is $4 a loaf, it is likely a silver dime will still buy a loaf of bread, as the price of silver rises too. In the 1930's, U.S. citizens' gold was (for all practical purposes) confiscated by the government; it happened once, it can happen again. I think silver is unlikely to be confiscated, although its purchase and sale may be controlled for so-called "national security" purposes. I'll be gone, you guys in your 20's and 30's, good luck with all that. And ALL my safety deposit boxes are at credit unions, not banks. There's a good reason for this, too much to discuss here.
I like the prices at Provident Metals and end up buying from them more often than not. They offer free shipping if you add one of these items to your order. Sometimes Apmex has good deals on their EBay page. As far as what to buy, I say buy what you like to look at. I only buy rounds and coins and put everything in airtites. After buying a bunch of different things to see what I like, here's what I've gravitated toward: 2014 Maple Leaf - I like the security features, will be easy to sell American Silver Eagles - everyone should own some of these, pretty and popular 2013 Mexican Libertad - beautiful coin! 2014 Britannia - people collect these, likely to increase in value over time regardless of the price of silver Veritas Lux Mea - Heidi Wasweet's latest work; lovely! If you have no idea what to get, start with American Silver Eagles (often referred to as ASEs online.) You can't go wrong with that coin.
One thing I'll add since you are new to bullion: Stick with a reputable dealer until you become familiar with silver. No craigslist or ebay for you. There are plenty of threads here about people getting stuck with fake bullion. Just search the bullion section for "fake". Provident Metals is very reputable and a good place to start. Or, if you have a reputable local coin store (LCS), they're also handy because you can examine the product in hand before purchasing. The premium is typically a little higher in a store, but at least you don't have to pay shipping, you don't have to wait for shipping, you can use cash, etc. (FYI - Provident sometimes takes a few weeks to ship, but I've never had a problem.) There's a thread here called "Post your silver bullion" and it might be a good place to familiarize yourself with what's out there: http://www.cointalk.com/threads/post-your-silver-bullion.167879/
