Please go to the admin page, product definition tab, and type in a new name in the product code box. The page should refresh to let you add the details of a new product.
From FAQ:
How do I manage products?
Looks like I can define only one product?!
To add a new product, type in a product code in the “Product Code” field. You can then specify the rest of the product details.
To edit an existing product, select it using the drop-down menu (or type in its product code.) The product will be loaded and you can edit its details, just like defining a new product.
Note that the drop-down menu is editable. To add a new product, just type in a new Product Code even when the drop-down menu looks like a menu. This is the point that confused some of my users, leading them to think that they couldn’t define new products.
