There are 3 ways to customize and personalize blogs at wordpress. Two options are available at wordpress.com and the third is available from wordpress.org http://en.forums.wordpress.com/topic.php?id=6406&page&replies=9
As you have linked your username here to your commercial website it will probably be a good idea for you to know that generally speaking, wordpress.com is for non-commercial blogs. You can confirm the advertising restrictions on wordpress.com blogs by reading http://faq.wordpress.com/2005/12/08/adsense/ Also note that if you have any advertising questions you can communicate directly with staff by using the feedback button on the top right hand corner of any blog page.
If you wish to have a commercial blog then you can hire a web host and have him or her download a free blog template from http://wordpress.org and, if you have blog contents already, you can export them out of your wordpress.com blog and into your wordpress.org blog.
The "please read me first before posting" sticky post at the head of the forum contains information that describes the differences between wordpress.com and wordpress.org http://en.forums.wordpress.com/topic.php?id=3700&page&replies=1