There may be a few of them floating around in more remote parts of the country, but it would be a very unusual occurrence to find one because it's been over 50 years since the last one was printed (March, 1964).
The Treasury never officially withdrew silver certificates - they simply halted redemption for silver metal, so they functioned exactly the same as Federal Reserve Notes. It was possible to find a few in circulation as late as the mid-1970s. Since then most would have either worn out or been saved because of their distinctive appearance.
All current circulation bills are Federal Reserve Notes so depending on the dates you're interested in you can simply look in your wallet. Older dates of Federal Reserve Notes (before 1999 depending on denomination) and all silver certificates are pretty much out of circulation though, so you'd need to look on eBay, go to a coin and currency show, or visit a dealer.
At the time silver certificates were printed, they could be exchanged at a bank for silver dollars. They haven't been redeemable for silver since 1968, though they're still legal tender at face value.
Older dollar bills are indeed still in circulation. US bills aren't removed from circulation until they wear out.
Silver certificates are a form of representative money used in place of actual physical silver, you can buy them on ebay.
When silver certificates were originally issued the government controlled the price of silver and had a large hoard in various locations as backing for currency. Only as many silver certificates could be printed as there was silver to back them up, so it was a way of controlling the amount of money in circulation and holding down inflation. Citizens were allowed to take silver certificates to banks and some government offices where they could be exchanged for an equivalent amount of metal. As the economy changed they only became exchangeable for silver coins, which made them effectively the same as other kinds of paper currency except that they still had to be backed by silver. By the 1960s market pressure on silver (much from the electronic and photography industries) forced the government to deregulate its price and start selling its hoard. They stopped printing silver certificates and abandoned the policy of exchanging them for metal. By 1963 all U.S. currency printed was either Federal Reserve or U.S. Notes, which were not backed by any metal in the Treasury. U.S. Notes were discontinued shortly after that, around 1966 because they were entirely equivalent to FRN's.
The coin is still found in circulation and is face value
Silver certificates were never officially withdrawn. After the price of silver was deregulated the Treasury simply stopped redeeming them for silver metal and declared them to be equivalent to Federal Reserve Notes, with no precious-metal equivalency. Silver certificates gradually wore out and were replaced by new FRNs during the normal course of currency replacement. They occasionally showed up in circulation well into the 1970s, possibly later in some parts of the country.
It's not silver, no SBA dollar was struck in silver. The coin is still in circulation and only a dollar.
The last silver certificates were printed in the early 1960s, although they were dated 1957 B. During the 19th century silver certificates were at some point printed in every denomination from $1 to $1000. Only $1, $5, and $10 bills were printed as silver certificates during the 20th century. When the price of silver was deregulated the government could no longer exchange silver certificates for a fixed amount of metal, so redemption was halted to prevent people from speculating on price fluctuations. Because they were no longer "convertible", silver certificates became just like other bills in circulation. There was no longer any need for separate types of paper money so production was stopped. By 1969 all $1, $5, and $10 bills were issued as Federal Reserve Notes. Silver certificates remained in circulation but gradually disappeared as they wore out.
The coin is only face value, has no silver and is still in circulation.
Silver certificates from 1957 are no longer in circulation as legal tender, but they can still have value as collectibles. The exact value of a 1957 silver certificate bill depends on its condition, rarity, and demand from collectors. You may want to consult with a currency expert or check online marketplaces to get an idea of its worth.
50 cents, contains no silver, and is one of the most common half dollars in circulation.
It's a common coin, still in circulation, has no silver and is just face value.
The first silver certificates were issued as $10 bills in 1878. Other denominations soon followed. $1, $5, and $10 were the most common but at one time or another silver certificates were printed in every denomination up to $1000. Printing of silver certificates were discontinued in 1964 (some sources say 1965) when the price of silver had to be deregulated due to increasing demand, although all of these bills were issued as part of either the 1935H or 1957B series. Redemption for silver metal ended in 1968. Silver certificates have never been withdrawn and are technically still legal tender, but essentially none remain in circulation after nearly 6 decades.
The coins are still in circulation, contain no silver and are face value.
Occasionally old silver U.S. dimes, quarters, and half dollars show up, but most have been pulled from circulation by collectors. Silver coins are seen less frequently in other countries that have redesigned coins since removing silver.
The 1967 Washington quarter has no silver and is still in circulation, the coin is face value.