Wants to Register a Trademark for eBooks

Dear Rich: I am writing a series of travel eBooks that will be published for use on Amazon's Kindle. All of the book titles share a common phrase. I also have website and the domain name is the same phrase as used on the books. So far, I've only written about one city. How do I protect the phrase so some other publisher won't use it? I am not sure if there will be any other products beyond the eBooks, but I would like the ability to brand the phrase for use on other products -- for example, maps, T-shirts, or mugs. If you are registering the title for paper books and eBooks, you would register in Class 16 (paper goods) and Class 9 (downloadable content). If you wanted to register your name for use as business website, you would register in Class 41 (education and entertainment services). Each registration permits you to stop interlopers infringing within the class of goods or services (or closely related goods and services, too). Therefore, even though you are only producing eBooks (and would file in Class 09), if you intend to also offer printed books, you may wish to "reserve" trademark rights in Class 16 as well. (We're aware that at $275 per class, these registrations can become expensive).
Book marks ...  Keep in mind that you can't register a single book title as a trademark, only a series of book titles (see our previous entry). So before filing as a potential trademark for books, you would need to show the examiner that you have a series, not just one book -- for example, the Dummies books are a series, as are the Harry Potter books.
How to proceed ... Because we're not sure of your grand plan -- for example, whether you want to use the phrase as the name of your publishing business -- we'd suggest you consult with an attorney. If that's not possible on your budget, consider filing a registration in Class 9 (assuming you're convinced you have a series). As for the other goods you mentioned, you would need to file separate registrations for mugs (Class 21; household items), and t-shirts (Class 25; clothing). As for maps, those might be covered if you filed in Class 16 for paper goods.