perform look up without creating relationship
I have a file with client information and services they have bought and I want to do a lookup of the cost of those services. I also have a file with all the services and service costs. Is there a way to do a lookup without creating a relationship between these two files? I would like to do the lookup without a relationship because in order to have a relationship I need to have a common field value between the two files. My intent is to perform a lookup or create a script that will allow me to push a button and go to the cost file but I even need a relationship to tell the script to go to a different file. Any suggestions?