The multiple prices come from Paypal "options". I call the field Registration Types, since that's what I'm using EME for and what the ticket types are.
The code loops through the list of attributes to find anything ending in PRICE and uses that to build the options selector for the multiple prices.
It goes with the form to display the Paypal button, and is in my originally posted code if you want to see it in context.
Let me know if this isn't clear.
$display .= '<!-- Provide a dropdown menu option field with prices. -->'."\n";
$display .= '<input type="hidden" name="on0" value="Registration_Type">Registration Type<br />'."\n";
$display .= '<select name="os0">'."\n";
$dis2 = "";
$attrib_counter = 0;
foreach ($eventinfo['event_attributes'] as $attrib_name => $attrib_value) {
if (strpos($attrib_name,"PRICE") !== FALSE) {
$attrib_name = str_ireplace ("_PRICE","",$attrib_name);
$display .= '<option value="'.$attrib_name.'">'.$attrib_name.' - $'.$attrib_value.' USD</option>'."\n";
$dis2 .= '<input type="hidden" name="option_select'.$attrib_counter.'" value="'.$attrib_name.'">'."\n";
$dis2 .= '<input type="hidden" name="option_amount'.$attrib_counter.'" value="'.$attrib_value.'">'."\n";
} // close if PRICE
$attrib_counter++;
} // close foreach
$display .= '</select>'."\n";
$display .= '<br />'."\n";
$display .= '<!-- Specify the price that PayPal uses for each option. -->'."\n";
$display .= '<input type="hidden" name="option_index" value="0">'."\n";
$display .= $dis2;
