There are many places. Mostly online. See the related link for an online price guide.
You can find the coin set for about $50.00. Most retail will sale for $60-$65
June 22, 2009. You can find this coin priced in the $30 - $40 range but they can be easily bought for about $10.
It is not very easy to find out the value of a 1878 morgan silver dollar, because the value varies from $20 to $46000 which depends on the condition of the coin. A specialist could help to find the value of this coin.
Currently the San Francisco mint only produces proof coins. Every so often someone breaks up a proof set (accident / theft / ignorance) and spends the coins for their face value. However, once circulated, a proof coin loses whatever premium value it had when it was in its sealed package. Look at the edge. If it's copper-colored you have a clad coin made of copper-nickel. In this case you can certainly hang onto it as an interesting find, but it unfortunately doesn't have any extra value. If the coin is lighter in color than a normal quarter and doesn't have a reddish edge, you probably have a silver quarter from a premium proof set. Even after circulation, the silver in it would be worth around $3.
You can take it to a coin dealer and have it appraised.
Quarters, halves, and dollars were minted with the dual dates 1776-1976 as part of the Bicentennial celebrations. Loads of them were saved in new condition as keepsakes so any that you find in circulation will be worn and only worth face value. If you have an uncirculated or proof Bicentennial coin please post a new question with its denomination and what type it is (unc. or proof); if it's a proof coin note whether it's made of copper-nickel or silver.
This is not a US Mint issue coin it's a novelty coin of some type. It could have value if it's made from silver. Look for the marking of .999 fine silver on the coin. If you find it, it's made of silver and does have some value.
It depends on how much silver is in it. Casinos use a multitude of different sizes of coins. Take your silver coin, find the weight in troy ounces then multiply it by silver spot price (at the time of writing it is $29.30). Casino coins have very little collector value and any value comes from the silver content in the coin.
Any you might find that were in circulation are still worth a dollar. The only ones worth more are the silver or proof coins, all minted in San Francisco.
The only reference I can find to a 2007 Australian 1 Dollar coin featuring a Koala is to a pure silver 1 ounce coin with a current value of about $30 AUD. It would probably be suitably packaged in a case.
Quarters, halves, and dollars were minted with the dual dates 1776-1976 as part of the Bicentennial celebrations. Loads of them were saved in new condition as keepsakes so any that you find in circulation will be worn and only worth face value. If you have an uncirculated or proof Bicentennial coin please post a new question with its denomination and what type it is (unc. or proof); if it's a proof coin note whether it's made of copper-nickel or silver.
"Melt Value" refers to the value of the silver content at the current "spot" or raw silver price on the commodities market. These values change daily. If you can find a market quote for current one-ounce of silver, multiply that by 0.18084 (which is the pure silver weight) to get the value of one US Quarter dollar coin. Note that most such quarters were minted with dates BEFORE 1965 (with the few exceptions of some Proof Coins minted since the 1980's).