I have my own domain hosted with Blogspot. I'm happy because I don't have to pay for hosting and I never have to worry about my site going down.
here is bloggers help article for changing your domain:
Blogger Help : How do I use a custom domain name on my blog?
I would buy the domain with Godaddy so that if you have any problems you can call for technical help. They're open 24/7 and have helped me a lot.
Crystal
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