Populating multiple fields from one database to another
I'd appreciate help on the easiest way to populate a selection of fields in my invoicing database using info I already have in my customer database, such as customer name, company, street address, city, state, postal code and email address. The idea is to type in a customer's name in my new invoicng database, then press an update button that retrieves the above info from the old customer database. This will spare me the ordeal of typing the whole lot in each time I create a new invoice.
I've attempted using scripts and relationships but I'm such a novice and keep running into trouble.