VLookups in a Contact field

I would love to be able to have one table with contacts (i.e. administrative support personnel) and use a Vlookup function to insert the correct contact into a row on another table.  We have a lot of turnover in those positions, so it would be nice to be able to update the separate Administrative table and then let it update my contacts for each row in my other table.    Everytime I try this, I get an error right after I link to the other table and it won't even let me finish the Vlookup formula.  Does anyone know of a way to make a Vlookup work in a contact field.   I want to keep the column set as a contact field so that I can set automatic alerts and update requests to the contact in that column.  Thoughts or ideas?