vLookup location based on link in adjacent cell

I have a worksheet that gathers and consolidates monthly financial data. There are 2 columns for each month. Left column is location information, right column is account information. Currently, I run a vLookup and manually point each cell to the appropriate data source (a workbook sitting on our servers). What I'd like to do is have a designated cell that sits above the 2 columns that I could simply drop a file-link into and have the vlookup reference table_array looking at the cell that I just dropped the link into.

Also, the location of the data workbook never changes, so in a separate cell, be able to have an H:AA input... Somehow tie these together in a vlookup so all the user has to do is copy/paste the file link into a specific cell, and in another cell indicate which column number to look at.... Something like the following.

=vlookup(A4,B1&C1,D1,0)

A4 = title of metric we're looking for
B1 = link of data sheet that's on server
C1 = the cell reference in data sheet on server
D1 = how many columns to the right to look.

This is a bit tough to explain by text, please let me know if an attachment example would help.

Thanks to all contributors!