Need formula to calcuate from multiple worksheets that have their own formuals

I have a quarterly sales tax spreasheet with use for our company that I created. Each month I need to input all the paid invoices and include the city, taxable, non taxable, etc. I created a drop down for the the city, which then auto populates the appropriate sales tax and which county. I now need that info to auto populate into the county portion of the quarterly worksheet which is named "QE 02 13".

See attached.

Can anyone help? Also, don't use this attachment, see the one further in the thread. This one has a password.