Microsoft Excel 2003

I have a workbook with several worksheets, within the workbook I have a master worksheet that has a compilation of all the other worksheets. What I need to happen is I want to add the total columns in the other worksheet and display the totals on the master worksheet; the issue is, not all of the items are uniform across the workbook, some share values, while some have just a few.
I tried to create a formula to scan within a certain range and only sum up the third column if the values in the first column match; below is what I have come up with that is not working for me, if anyone can solve this for me I will be your new best friend.
=IF(‘256th IBCT NG 0409:2-2 IBCT’!A2=A2,SUM(‘256th IBCT NG 0409:2-2 IBCT’!C2),”0″)