Hi Dave...
Yes, this is possible. You're looking for search paths. This feature gives you the ability to specify a list of directories Creo should check for components. If you load an assembly and a necessary component isn't located in the current working directory, Creo will start running through the search paths to find the missing model.
To specify a search path, you can either add one new line to your Creo configuration file for each new folder you wish to search or you can add one single line to your configuration file that references a separate text file containing many lines.
Technique #1: Add individual lines for each folder
(1) Go to File->Options->Configuration Editor.
(2) Click Add
(3) Type search_path into the option name field of the window that appears (as shown below)

(4) Enter the folder you wish to search in the option value field.
(5) Select OK to add the search path. Repeat this process for each new folder.
Technique #2: Add one line to the config file and reference an external list
(1) Go to File->Options->Configuration Editor.
(2) Click Add
(3) Type search_path_file into the option name field of the window that appears (as shown below)

(4) Enter the pathname to a search path file into the option value field.
(5) Select OK to add the search path file pointer.
(6)Create/Edit the search path file listing as a text file. A sample text file showing the way to set up a search path file is attached to this message.
Make sure the pathname to the search file you set in Step #4 is correct or Creo won't read your search paths! Consult the help files for search paths for more information.
Let me know if you have any trouble!
Thanks!
-Brian