To make a Macro available to all your Excel Spreadsheets save it in the following:-
Early Versions of Office Loaded All Macros in the folder %appdata%\Microsoft\Templates\ folder
Windows XP Excel 2010
%appdata%\Microsoft\Excel\XLSTART\PERSONAL.XLSB
If this file opens every time you Open Excel then do the following:-
Open Excel
Click the VIEW Tab
Click Hide
Close Excel
Click Save
Now when you open Excel it will open Book1.xls
Windows 7 Excel 2010
%appdata%\Microsoft\Templates\PERSONAL.xltm
A Macro Enabled Worksheet