If you want to have a small business in this, then treat it like a business.
Purchase a .com domain. It’s 10-12 bucks.
Purchase a VERY SMALL hosting plan. I recommend HostGator.
install wordpress and work on your site.
A self-hosted with its own nice domain blog will ALWAYS be better than something you just made on blogger. It will make your potential advertising clients see you as a professional and the price (30 bucks/year or similar) is not that huge even for a startup.
I didn’t like blogger.com as my first - I ended up using webs.com and then later a self hosted wordpress. If I was going to do it all over, I would have gotten my own hosting and done a wordpress self hosted blog right from the start - otherwise my second choice would be wordpress.com or posterous.com