I'm using Imageshack.
http://www.imageshack.us/
after you host the picture, you'll see some adress of picture.
and copy the adress of "Hotlink for forums (1)".
adress is will be shown like this
[URL_=http://imageshack.us][IMG]http:/img84.imageshack.us/img84/2713/conv00023cs.jpg[/IMG][/URL_]
and, delete
"[URL_=http:/imageshack.us]" and "[/URL_]"
that's it.
sorry for my bad explanation.