I'm trying to create a VLOOKUP for billing purposes. I need to have the number of last month's documents in the current month's billing information. I have the VLOOKUP working with no problems, but I want to name the sheet after the month and have the VLOOKUP reference a cell for the sheet name. So far I have:  
=VLOOKUP(A4,INDIRECT(CONCATENATE(B1,"!")),A:G,7,FALSE)
where A4 is  Project Name
B1 is Previous month (ie July2014)
A:G is the table array on the previous month's sheet
in which it is column 7 that contains the closing document count.