To qualify one of the earlier answers to this question, if you buy US 90% silver coins that are only dated in the 1950s and early 1960s (1964 and earlier), these coins are a) likely to be of higher grade and b) not very likely to be "culls" - damaged coins. Those coins didn't have a very long time in circulation before the US stopped minting 90% silver coins, after which all such coins were hoarded. For that reason, you can often find silver coins from the early 1960s in near uncirculated or even uncirculated condition, even in mixed lots of 90% silver coins.
You can buy bags or rolls of coins, whether on eBay (which you said you don't want to deal with) or from coin dealers or bullion dealers, that are only in those date ranges. Those date ranges include only the following: Roosevelt dimes, Washington Quarters, and Franklin and Kennedy (the latter 1964 only) Halves.
A couple of coin/bullion dealers who list prices on the Internet seem to be offering 90% silver bags today, April 6, 2008, at prices of about 12.7-13.2 times face value, not including shipping and sales tax, if any. On eBay, most such lots seem to be going for around the same price, although that also includes shipping; most eBay sellers don't seem to charge sales tax, as well.
Of course, on eBay, by bidding somewhat lower on many auctions, occasionally you may be able to pick up some coins at a lower price; it's a fairly efficient market but not an entirely efficient one. That's much less likely in the case of coin or bullion dealers, who are usually experienced pros; even if you do a lot of shopping around, it'll be hard to find a bargain.
Finally, you might consider Canadian 80% silver coins as an alternative, perhaps alongside some US 90% coins. They often sell considerably below spot, so they're a better buy, silver-for-silver, and have the added benefit of not being as likely - all things considered - to fall under future Government restrictions.
In the 1967, the US Treasury severely limited what private citizens could do with their US silver coins. And in December 2006, the US Mint imposed criminal penalties on US citizens who melt or export even humble US pennies and nickels. (See the sources below.)