If you want the currency symbol to display you have a few choices, such as:
1. Use the NumberFormat.getCurrencyInstance() method to get a formatter that handles currencies.
2. Supply your own pattern which outputs the currency symbol.
Another question is, what if I wanted to make the currency symbol appear AFTER the number?
If you are using option 1 above, I would imagine the currency formatter will put the symbol in an appropriate location for that currency. If you want to change that behaviour then I believe you will have to supply your own pattern.
If you are using option 2 then you are supplying a pattern so you can put the symbol wherever you want
For details on setting your own pattern see the DecimalFormat classes API docs.