but the general principle is that any eBook you buy from Amazon is accessible from any device via Amazon's servers. Is there any kind of synchronisation or sign-in option on your iPad?

There's a free Kindle app in the iTunes store.

Simply install it and log in using your Amazon account, and you will be presented with a list of your purchased titles.

I just 'click' the selected book on the virtual shelf and away I go.

If you log into your Amazon account and look under Kindle / Manage Your Kindle, you should see the list of books you have bought. On the left of the page you should see your Kindle account details and the option to manage your devices. Once you've added your iPad, go back to the list of books and click on Actions to deliver to your iPad. I think that should work, although I've got an actual Kindle rather than an iPad.

and they just appear in the Kindle library - no sync-ing needed.

is logging in both devices to the service using the same Amazon account id. Then the Whispernet feature should sync them all automagically, including where you are up to. Does your iPad have internet access ? Not sure how you'd do it if you simply tether it to the Mac

Dear all

now done and thanks for all the help.

KGB