Two types of $20 gold coin were struck in 1907. If you have a coin with Miss Liberty's head shown on the front, look on the back to see if there's a small mint mark letter below the eagle. It may be blank or there may be a D or S.
Numismedia lists the following approximate retail values as of 05/2010:
No mint mark (Philadelphia):
Very worn condition - $1,500
Moderately worn - $1,620
Slightly worn - $1,670
Almost no wear - $1,722
Uncirculated - $1,800 to $9,520 depending on quality
"D" mint mark (Denver):
Very worn - $1,500
Moderately worn - $1,620
Slightly worn - $1,670
Almost no wear - $1,722
Uncirculated - $1,800 to $76,280
"S" mint mark (San Francisco):
Very worn - $1,500
Moderately worn - $1,620
Slightly worn - $1,670
Almost no wear - $1,722
Uncirculated - $1,800 to $27,680
If the front of your coin has a full-length image of Miss Liberty holding a torch, and the back has a soaring eagle, it's called a St. Gaudens variety after its designer and should be evaluated by a dealer or appraiser. Different varieties of the St Gaudens design were made in 1907 and their values range from those comparable to the Liberty Head variety, all the way up to about a quarter of a million dollars.
In circulated condition -- about $1100 as of 08/2008
Nice uncirculated ones go for more, depending on exactly what grade they are and whether they are with or without motto.
For historical reasons the US never struck a $2 gold piece, but instead minted the odd denomination of $2.50.
If your coin is a $2.50 piece, please see the Related Question for values.
Current retail values for circulated coins are $178.00-$312.00
Around $140 if very worn, up to about $200 in nearly-new condition.
In order to give an accurate estimate, the coin should be seen. I suggest you take it to a coin dealer and have it appraised.
Assuming the coin is circulated and has no mintmark, retail values are $350.00-$510.00 depending on the actual grade of the coin. The value just for the gold is $292.00
Current value is $109.44
Current retail value for a certified 1908 Half Eagle is about $5,000.00 in MS-64
about 13.000 euro
As of today about $250.00
It's NOT gold and just a dollar. The last year the US made a one dollar gold coin was 1889.
About $325, for its gold content.
1896S .999 fine gold
2009 50 dollar gold piece 1oz worth money value
It's worth exactly one dollar (and it's made of brass, not gold).