VBA code for VLOOKUP - linked to another workbook

[Andrew]

Hello,
I'm looking for a way of putting a drop down box into a user form.
The drop down box will work as a VLOOKUP function. The list used for
the drop down box exists in another workbook. So, in a user form, I
need a drop down list which populates itself from another workbook.
Once a user clicks on an entry in the list, the drop down list acts as
a VLOOKUP function. Does anyone know how to do this? If so, please
send me an example code.

thanks