Mail - backup and restore

I'm changing broadband supplier and want to backup mail and address book before the migration.
I cannot see how to backup.

I have a write-up from:
Mac Mail - Backup & Restore
but I cannot follow their instructions because "........ under the Mailbox option select 'Archive Mailbox'............ there is Archive option in my Mail menus!!

I'm using
Version 5.2 (1278) of Mail
and Mac OSX 10.7.4

I don't know if this is what you mean, but you can create an archive of both Address Book & iCal by selecting (in each case) File/Export/Archive and saving to wherever you want.

As for Mail, you can export & save your Mail Boxes in the following manner:

You can export a mailbox to create a backup copy of it, so that later you can retrieve messages from the mailbox if you need to.

Select one or more mailboxes to export.
To select mailboxes that are next to each other (contiguous) in the list, hold down Shift as you click the first and last mailbox. To select mailboxes that are not next to each other in the list, hold down Command as you click each mailbox.

Choose Mailbox > Export Mailbox, or choose Export Mailbox from the Action pop-up menu (looks like a gear) at the bottom of the sidebar.
Choose a folder or create a new folder where you want to store the exported mailbox, and then click Choose.
Mail exports the mailboxes as .mbox packages. If you previously exported a mailbox, Mail does not overwrite the existing .mbox file but appends a number to the filename of the new export to create a new version, such as My Mailbox 3.mbox.

This is copied from Mail Help.

All these work as above. I do this relatively frequently and backup to a EHD just in case of catastrophic failure.

Hope this helps you.

Ian

Thanks Ian that is just what I wanted.
BTW, your avatar, where is that lovely spot.

The "lovely spot" is Deganwy in Wales (close to Conwy, if that helps). I live here.
I'm glad I was able to help.

Ian