You can use the list web service to pull the list structure and get the URL to the attachment, from here you should also be able to add the attachments to the new list.

I did something similar for a forms library in wss 2 to 2010.

If you have access to the server you can use the object model to do that.

If the two SharePoint environments on the same domain you could use one of the migration tools that are on codeplex

You can use the list web service to pull the list structure and get the URL to the attachment, from here you should also be able to add the attachments to the new list.

I did something similar for a forms library in wss 2 to 2010.

If you have access to the server you can use the object model to do that.

If the two SharePoint environments on the same domain you could use one of the migration tools that are on codeplex

EDIT

Here are a few links to some free tools that will help you:

Can run on Client machine:

http://www.messageops.com/software/office-365-tools-and-utilities/office-365-sharepoint-migrator

Runs on the sharepoint server: http://consoledocenum.codeplex.com/

There are other tools out there but i hope this helps

Cheers Stephen