In my "Main Board Parts" tab I use the following in one of my cells:
=IF(ISERROR(VLOOKUP(TRIM($H34),Inventory!$M$2:$W$1 350,11,0)),"Not
Found",VLOOKUP(TRIM($H34),Inventory!$M$2:$W$1350,1 1,0))
A "Not Found" message is returned if the number I'm looking for does not
exist.
I also use the Trim feature to make sure there are no spaces in the text I'm
looking for.

H34 is a number, in my current workbook tab (Main Board Parts) I want to
look up in my workbook's "Inventory" tab.
M2 thru W1350 are the rows of data I look thru so I can find what I'm
looking for in my main Inventory worksheet tab.

Here is what I would like to be able to do; when I add more columns to my
inventory tab, my VLOOKUP doesn't always update the W1350 value in the
formula string.
I would like to have two cells that have the values M2 and the W1350.
Now when I add more columns I don't have to go thru and re-modify each
formula throught out the workbook.
To give you a rough idea on how big my workbook is; the inventory page is
~50 rows wide and over 1350 columns long. I have over 30 tabs and the tabs
range from 10 rows to close to 100 rows long each.

Here is what I want it to look like:
=IF(ISERROR(VLOOKUP(TRIM($H34),Inventory!$M"Formul a!A1":$W"Formula!A2",11,0)),"Not
Found",VLOOKUP(TRIM($H34),Inventory!$M$"Formula!A1 ":$W$"Formula!A2",11,0))

In the "Formula" tab:
A1 = 2
A2 = 1350

How can I make this work?