Hmmm, CMIIW…. We can’t use adsense in wordpress.com so i’m not wondering if I can’t find theme editor in “online” version free hosting in wordpress.com

If you want to edit your theme, including sidebar, header,etc. you should find hosting and domain services. Plug your wordpress there and start to modify…

This is another differences between wordpress and blogger. Anyway, this is a good start, i’m learn a lot from this experience.