Help with finding specific number and returning the right sum

You'll have to excuse me, I'm not quite sure how to word this. I think the formula I'm thinking of is either HLOOKUP or VLOOKUP.

Basically, I have multiple worksheets in one Excel document, I want a formula the searches each different worksheet, checks to see if there's an ID code (which I'll specify) in the worksheet and return the sum of products sold to the "main" worksheet.

I hope that makes sense! I've attached the Excel document as an attachment if you need to take a look at what I mean.

Thanks for any help in advance!