Modify macro statement

In the following statement I need to be able to replace the QT1 with a stock symbol. Since someone may wish to obtain several sets of data, for several symbols, the replacement will have to be done through a loop.

Workbooks.Open Filename:= _
"http://ichart.finance.yahoo.com/table.csv?s=QT1&a=07&b=25&c=2006&d=08&e=24&f=2007&g=d&ignore=.csv"