steve,

You're on the right track. Re. linking of subforms to parent, the
easiest way is to activate the Control Wizards in form design, if not
already active (the button with the magic wand on the Toolbox toolbar),
and then add the subfoms; the pertinent wizard will kick in, and force
you to select controls on either side (main / subform) to link on.

If you already have the subforms in place, toy can do it manually by
selecting each subform in turn, and changing the values in the Link
Child Fields / Link Master Fields properties on tab Data (or click on
the button with the ellipsis sign that appears on the right of the
property when you put the cursor into it, to invoke the wizard).

HTH,
Nikos