custom product 'meta' info

Hi,

I'm looking to setup a store using marketpress in order to sell books.

Is there any way I could add meta information on a per product basis such as author, isbn numbers, publisher, publication date in such a way as they are searchable, but without using the 'Product details' section which results in an inappropriate (for this purpose) dropdown.

I'd thought of using tags, which might work for publishers, authors etc... but is useless for the ISBN numbers. Even for publisher or author, using tags is agnostic towards what the tag _is_, so the ability to add meta info as key/value pairs would be the better solution, but doesn't seem to exist for products within marketpress, unless I'm missing something.

I would also need to be able to display this information in a structured way at the top of the product description, so again, having key/value pairs available through some meta information would be helpful.

Thoughts?

Rob