Pages, from the App Store, or even (cough) MS Office for Mac.
Failing that, your "blog" software should cover what you want to do.
I have a website at http://www.hilfandhilf.com which provides blogs concerning different immigration and criminal law issues. I am looking to purchase a word processor for the primary purpose of writing and eventually publishing blogs, and modifying those blogs to create additional web pages. What word processor is easiest to use and integrate with my website software?