I have an online application that pushes all of the data to Account/Contact/Deal.   The problem I am having is that there sometime is an open lead with that person.   Is there a way, other than manually to check to see if it is a lead and convert that lead to Account?  Or is there another work around?   Here is my scenerio.....

Today I did a webinar, zoho meeting pushed the registrants to leads.....hours after the webinar, one of the registrants went online and filled out our application, creating a Account and Contact.   If they forget to check/convert the lead, we can look like idiots marketing to the lead that already signed up.

Any help is much appreciated