In old Blogger it used to be slightly easier to add a profile photo, but such is life!

There are two methods. One is for the adept. The other is for the technically challenged.

To add a profile photo in New Blogger:

Open up your "create a post". Upload a picture of yourself into the post. Click on the "Edit Html" tab of the post box. The beginning of the picture link will look similar to this:

<a href="http://bp1.blogger.com/_m32TlugOPkM/ReuwAwZZiaI/AAAAAAAAAHE/YCYPlCGOxR0/s1600-h/construction.gif"><img border="0" id="BLOGGER_PHOTO_ID_5038314135181953442" style="display:block; margin:0px auto 10px; text-

The part highlighted in grey is what you want to copy to the profile photo URL box. Note: Yours may say .jpg instead of .gif!

The second way is to upload the picture to a post. Publish the post. Click on the photo. It will open up on a white page. Copy the URL that is in your browser address bar at the top of the screen