i'd go immediately to the livechat mob - they'll tell you how to go about not only reporting her behaviour, but what recourse you have re negative feedback, getting your money back etc. i seriously doubt she'll part with the pram for you now - all they can really do is cancel the listing and hope that she is desperate enough to hand it over for the $40 you paid for it - by the sounds of it, she won't though
good luck with this hun

