Let me give you two options. There are probably more:
1. Have the "sub" forms be pop-up forms that open on the Command Button click. You can then use the "Where" clause of DoCmd.OpenForm to dictate which records should appear, making it behave like a subform.
2. On my main form, I have a subform whose Control Source I change with a click in a list box. In other words, many subforms are displayed in the same control (place) on the form. If you have User-Level Security, there are issues (you need to give everyone design permissions on the subforms) but that may be a way around your problem.
HTH