If you've signed up to a trial after 19th August you can create new reports and move coverage between reports easily using the All Coverage view. Here's how.
It's easy to make new books out of existing ones. You can duplicate and merge existing reports to make new, larger books!
Head to the main "my books" area, then find the report you want to copy. On every report there is a "copy" option. Hit that and a duplicate will be made.
You'll notice there a "merge" button next to his if you're looking to combine reports as well. See here for more.