ImageShack and Photobucket are websites to post photos on.
This is how I put a photo up next to my posts:
I used Paint Shop Pro (any paint or photo program will do)
First I made a new Image of 83x83pixels. Then I got the photo I wanted and loaded that up in it's own window in PSP. I reduced the image so the part I wanted to use (The head) was small enough to fit in the "new image" window.
After that I copied the resized photo and pasted it into the 83x83pixel new image window as a new layer. Then I moved it around until I got the part of the photo I wanted lined up and merged the layers.
With my new photo the correct size, I saved it to the desktop. I went back into "Profile" on here (FF). I told it where the image was and it uploaded it for me.
-Alternattively you can just crop the photo you want and resize it. Then save and upload that image.