There isn't an out of the box way to do this unfortunately.
You will have to assign someone to do this on a regular basis, such as an inside salesperson.
Another option is to hire a developer to custom code a solution for you that would automatically create these leads in Marketo via an API.
Yeah I figured it would require some coding. I'm checking with our IT department to see if anyone has the skills if not I have contact as long as he's not too busy.