Find Maximum Address
John Walkenbach, Excel 2002 Formulas, http://j-walk.com/ss/books/bookxl21.htm
{=ADDRESS(MIN(IF(A1:A10=MAX(A1:A10),ROW(A1:A10,"")),COLUMN(A1:A10))}
Enter the formula as an array (Push Ctrl, Shift and Enter simultaneously)
An alternative from Juan Pablo Gonzales
=CELL("address",INDEX(A1:A10,MATCH(MAX(A1:A10),A1:A10,0)))