Below is what I wrote for another user who had also asked about pictures. Adding pictures to a posting or your "Signature" in your member Profile is basically the same process. The link to the posting a States Visited Map will explain how to update your Signature.
I wrote up an instruction sheet some time ago on posting a "States Visited Map". http://www.montanaowners.com/forums/...ad.php?t=40564
The States Visited Map is a JPG just like pictures. So ignore the part about creating the map and start with uploading the picture to a hosting site. The MOC doesn't store your pictures (I have no idea why). So you have to find a site which will store it for you. Two popular sites are www.tinypic.com
Tinypic doesn't care who you are but if the photo isn't accessed for a long time, they delete it. Photobucket wants your name and email address, but in return they don't delete your pictures if they aren't viewed for some time.
I am a Tinypic user and the write up pointed to shows how to use that method. The intended destination for the States Visited picture was someones signature. But you merely paste the IMG tags and text into a posting to have a picture appear in your posting.
Email me at firstname.lastname@example.org
if the writeup isn't clear or you are a Photobucket user. I know how it works in Photobucket also (a little different from Tinypic).
Both products will resize your picture for you to fit the MOC size requirements (800 x 600 maximum).
Holler if you need help. Email is so much easier than using MOC PMs.