This is for me the problem of the decade. I have never spent more time on a problem more than this one. It is driving me crazy and I am feeling a heavy and maddening pressure on my head. I am about to punch my 500$ monitor. I have called everyone I knew and still nothing. You are my last hope.
In my opinion whoever can solve this problem is super genius, and not only the man of Excel, but the man of office-computing.

Here we go:

I have a workbook with 7 sheets in it. All of the sheets have only two columns, the first column contains plain text and the second column contains numbers. Each of the sheets are alphabetically ordered based on the first column. They look like this:
Sheet1
Title Score
A 2
B 8
C 52
D 10

Sheet2
Title Score
A 54
C 2
D 12
F 2
G 3

Sheet3
Title Score
A 12
B 2
C 89
E 1
F 10
G 91
H 1
I 12

Now What I want to do is to merge all these sheets, into a new one, in a way that the result sheet has two columns, Title and Score, as well. And at the same time, I want all the items that are present in first columns of each one of the other 7 sheets(3 in this example) to be present in the first column of the result sheet as well. And I want the Score column of the result sheet to be the sum of score value(s) for each Item. So the result sheet for this example, accordingly, should be like this:

Results_Sheet
Title Score
A 68
B 10
C 143
D 22
E 1
F 12
G 94
H 1
I 12

What should I do?
Help me, the pain is eating me up inside.