I started adding pictures today to my posted messages. To add a picture that is stored on your computer you just go into the edit mode and click on the picture button at the top of the screen. It will allow you to browse for a photo stored on your computer or from somewhere else on the Internet where a photo is stored.
After inserting a photo from my computer I was having trouble sizing the picture- the text wouldn't line up correctly around the picture. To resize the picture you can go into the edit blog view and then click on the picture. This will allow you to change the size of the photo so you can line it up correctly with the text (if that makes sense). Then you can see your picture along with your blog.
I also added a poll about underwear on my blog. What color is your underwear?