Yep. The real easy way is to put the pic that you are wanting to be sent in to your GJ album. As you are typing up a PM to be sent, just look to the left in the User CP options and click on "pictures /albums". ....
Open your album and right click on the pic you want to send and click on "copy picture". Then, click on the yellow envelope symbol above the message box and when it opens, right click on it and click "paste". ...
Before sending your PM just drop down and click on "preview" to see if the message / pic is what you want to send. Any pics (if allowed) on the internet can be done the same way and pasted in to your PM "insert image" box....
Also, using a photo host like Photobucket for ones' pic storage is good too. Their pics can be inserted as a link in to the PM text box by using the "Insert Link" icon above the text box. YMMV in accordance to your PC/ OP system.