Form example in context of page callback

I'm not really sure how that helps me.. here's more info about the module I've written:

/**
 * Implementation of hook_menu().
 */
function wpapers_menu() {
	$items['white-papers'] = array(
		'title' => 'White Papers',
		'access callback' => true,
		'page callback' => 'wpapers_list',
		'type' => MENU_NORMAL_ITEM,
	);
	return $items;
}

/**
 *  Implementation of hook_theme().
 */
function wpapers_theme($existing, $type, $theme, $path) {
	$hooks['wpapers_list'] = array(
		'template' => 'wpapers-list',
	);
	return $hooks;
}
/**
*	Page callback
**/
function wpapers_list() {
	//shows the form at the top (select menus) to filter the list of white papers
        // by means of  drupal_get_form() & loading that form into a variable so it 
        //can be printed in the .tpl file.
        //also shows list of selected white papers
        ...
        $data['content'] = ...the list of selected papers
        $data['filters'] = drupal_get_form('wpapers_filter_form');
        return theme('wpapers_list', $data); 
}

function wpapers_filter_form_submit($form, &$form_state){
	variable_set('white_paper_ind', $form_state['values']['industry']);
	variable_set('white_paper_prod', $form_state['values']['product']);
}

function wpapers_filter_form($form, &$form_state){
  //builds a form with select menus to filter the list of white papers by taxonomy terms 
  //uses variable_get to pre-select the filters.
}

How can I do this without storing to the db? I've even tried accessing the $_POST directly, but somewhere in the process it's getting blown away or overwritten...

Well - I'm just looking for help understanding how the passing of data is supposed to work with forms-to-pages.. maybe this isn't the right place...

The page callback is working fine, my form appears on the page along with the list of content. When I submit the form, the submit function runs, great - but how do I get data from that submit function back to to the page callback function to use it to filter my query.. without having to first store it in the db?

There doesn't seem to be a way to use form posted data on the page. All the form examples basically just print a message.

perfect, thanks.. that thought hit me this morning too - so a page redirect is the key, and then use the menu system with wildcard.. that should work! thanks!