I tested a listing through the add a listing feature. I noticed a few things... I was totally logged out simulating what a outside user would experience. When I clicked the button in the header and the add a listing, I received an error "couldn't find the page". When I logged in, it took me to the form to complete the fields. The form required a location and I couldn't move forward without one. Once I did I was able to add my listing and it created the pending listing before the pay pal payment was processed.
Seems like you deleted the Add New Listing Page and thats the reason you are getting the "Couldn't find the page error". Do look in your Trash and restore that page named "Add Listing". Yes, the listing appears as Pending until the Payment is completed, as soon as the payment is completed the listing is automatically moved to Published mode.
