Form Trouble

Hi, I am new to access but not to dBs. I need some help creating a form. I
have a table that contains customer information and generates a unique
customer number, custID, and I also have a table that contains a list of jobs
ordered by each customer. In the jobs table there is a custID which I want to
have a many-to-one relationship with the custID in the customer's table. So I
created a form that I want to select a customer from a drop down menu, which
contains Names and Addresses, and have it fill in the custID from the
customer table into the jobs table. As it is currently set up I can select
customers but it does not auto fill the custID. No data is transfered between
the two tables, even though I set up a many-to-one relationship between the
custID values in the relationships window. Any help would be greatly
appreciated.