If you contact your seller and ask to return the item, they are obliged to refund you via Paypal once you have returned the item to them.
However, considering they lied in the first instance about the condition of the listing; they might be totally unscrupulous and not refund at all; in which case it is a matter for Ebay & Paypal to sort out for you.
You should in the first instance file an 'Item not received' dispute; as you go through this process it will give you the chance to select the option 'Item arrived, but not as described'. This will send an Ebay email to the seller outlining your dispute. It is up to them to respond and Ebay will email you when they do so. Ebay do however always suggest to call your seller first; you can request a members full contact details from Ebay; I cannot quite remember the whereabouts it is on the site but if you use the links at the bottom of the home page, there is a 'safety centre' and if you use the search facility within this; you will be able to request the sellers details to be emailed to you. Then you can call them and assertively (!) tell them you are not happy and want your money back! :-D