Some very quick tips:
For a word, very short phrase, or a term, you'll be looking at a trademark. For a logo, you'll also want a trademark.
Copyright covers long written works or images. You would copyright a brochure design or website, for example. Copyright would also apply to an information product.
You can begin to "stake your claim" to the that you plan to apply for trademark by simply putting a TM after the word. After you go through the registration process, the TM would switch to the register mark, a circle-R.
And, you only have to put the TM or circle-R on the very first instance of the protected word or phrase – not all throughout the page.
For more information:
James S. Huggins has written an excellent book on trademarks for small business owners and entrepreneurs. It will help answer all the questions that the USPTO's site doesn't answer easily. It's a thorough resource and easy-to-understand. His Trademark Is Not A Verb ebook is on sale at his site for $17.00 – a real bargain for the quality information that it contains!
And, for the final word, please contact a lawyer when you've decided to get all official about your trademark – you don't want to set things up wrong!