I need an receipt for the plugin I downloaded

Hi I had troubles downloading Domain Mapping and muliple domains under the same account. I was asked to create a new account so that I could download domain mapping.

The accounts department now need the receipt but I dont have the invoice and cannot remember the account details i used to download the plugin. It would have been purchased around the same time as the multiple domain plugin.

How do I get a copy of this receipt?

Thanks Gareth