Please make my time sheet easier to work out

Hi, hope some kind person will help me out with my time sheet.. I have attached an example file. I work for a company that deals with shop etc.. They have done the time sheet for me to fill out.. however I'm not getting the right pay. The different shops are managed by a few Mangers who have a few shops each. My problem is my wage slip only list the shops and how much I get for that shop over a month. But it don't name the manager's on my time sheet. So when I'm paid short I can't pin down the person who is responsible. I'm not any good at Excel stuff, and so have to add up the sums one by one per shop.. the file I've attached has only a few of the place I work at. My actual time sheet is much bigger. So it takes me a considerable amount of time to work out how much I'm short. If I don't find a way to automate the adding up of the same named shops on the time sheet, I fear I will never get paid the amount I'm own as I can't get enough of the time sheet done to catch up before I get another payslip and so I'm well behind ever getting what I'm own. As an example of what I need the Shop named "Shop 100" if you add up the total amount I get £40.01. What would save me days,and probably weeks of "working out" would be some way of using the "lookup formula" to add up the total cost of the individual shops. If some one who knows about this kind of stuff could modify my "example file" and email me back an updated file that would automate the process.. ie maybe list the individual shops and the total cost associated with that shop; that would make my life so much easier. I got the "lookup bit" by examining the time sheet. I did attempt to work it out.. but to be fair, I'm not that clever.. I suspect that some of you would find this easy. I hope you will help me.. and I would like to thank whoever in advance for you time and effort..

John..