If you have a site selling personalized books (or anything else), adding a blog to your site can have a positive impact on your rankings in organic searches.
Adding a blog is quite easy. You can use free blogging software by WordPress. Your website host will probably put up a WordPress folder on your site for free. After they email you the login and password for your dashboard, you can sign in and be blogging in minutes.
Another way to blog is to go to blogger.com. If you blog on blogger, it is hosted for free and you can link to your blog from your website. One thing to consider is that if the blog resides on your hosted site, it is totally yours and under your control. If it is hosted by a service like Blogger.com, you could lose all of your blog postings if they decided to remove your blog for some reason.