Shopping Plugin (Suggestions please)

I’m going to make a shopping website and I’m looking for a plugin to simplify this.

The users however do not have to pay online, what happens is that when they click “At to order” it should go in their “shopping cart” and when they want to complete their order they have to fill out their details.

When they submit the form all this information should be send to an e-mail.

Problems I’m having:
How can I make WordPress remember that a product was added to the order and how can I add this information to the e-mail. Is there a plugin for this?

Thanks A LOT!