Change Currency Symbol
To change the currency symbol displayed, go to Admin->System ->System Settings. If you don't have the Multi-Currency add-on active, you can set the currency symbol and decimal places to display directly on the System Settings page. If you are using the Multi-Currency add-on, you can choose the Base Currency to use on the System Settings page. You can then edit the currency symbol and decimal places that are used by going to Admin -> System -> Currency New/Edit.
On the System Settings page you can also set the number of decimals to display for inventory quantities and set the time zone for your company.