Creating Filename From Cells

I have a worksheet that I would like where you can just enter the date, then it builds a filename based on that.

Example. Filename I would like to load information from is
"C:EXMay 2009May 21,2009.xls"
The sheet is "Data" and the cell/row is A1

The Filename could be entered simply as
'C:ExMay 2009[May21,2009.xls]Data'!$A$1

But what I would like to do, is be able to generate a weeks worth of filenames from the date I entered.

I have one cell with the root directory (lets say A1)
A1 = C:EX
A2 = May
A3 = 21
A4 = 2009

So in cell A5 I would like to combine them all to load the information from that filename.

I tried to do something along the lines of

A5 = A1 + A2 + " " &A4 (etc etc), but that wasn't working at all.
The main reason for breaking them up is so that I could just increment the date to get a weeks worth of files.