online bookshop

hi everybody. my company is planning to build an international online bookshop. This bookshop will have a data base of more then 10.000.000 titles. Those titles will be from countries all over the world. the data base will be handled from our side (partners from all over the world will be sending their data to us and we will upload the data to the onlines bookshop website. we need an advanced freight cost calculator which will have all the data needed for the cost from every country to every country of the world. Our eshop will be multilingual. The visitor from Spain for example will ask to see the Spanish interface, the one from Germany the German interface etc. When customers are looking to find a book in our database they will have the option to search in the whole database or the database of their preferance (for example just the books from Italy). When a customer for example from the US places an order for a book from Italy the order will go directly to the partner in Italy who will fulfil the order and send it to the customer. Ofcourse i need all the basic details of an e-bookshop (credit cards, returns etc).