For most people, the biggest purchase they make is their home. However, unlike some other assets it can be challenging to calculate the current value of a home. That's where the US Government can help. The Office of Federal Housing Enterprise Oversight
maintains a house price index
(HPI) for most metropolitan areas. The HPI is a weighted average of repeat sales, meaning that it measures average price changes in repeat sales or refinancings on the same properties. While the HPI is useful, take a pass on their calculator (it requires software downloads and is several megabytes.)
The HPI provides information about the movement of house prices, but other tools like HomeStore provide lists of home sales
in your neighborhood. If you're trying to calculate your net worth and you need to estimate the approximate value of your home, these two sites can help.