Multiple forms on single page?
If you want to add the same form multiple times, you need to implement hook_forms(). See node_forms() for an example.

This allows to use different form_id's, which all point to the same form builder function. For example, you can use yourmodule_some_form_$i and then use hook_forms() to point these to yourmodule_some_form.

See http://www.mohitsharma.net/content/how-show-same-form-multiple-time-page for an example