THE CODE: <img src:IMAGE_URL>
First, select the picture you want to put (embed - proper term) in the guestbook of your contact or on replies, or almost anywhere.. Right click on the image you like and select copy image location.
That image location is what we call a URL.
Now, here's the code you need: <img src=IMAGE_URL>
All you have to do is to replace IMAGE_URL with the image URL of the image want to embed.
Since we did copy the image URL via the right click, all you have to do is to right click again, and select paste.
Here's an example:
Let me do it with the headshot of this group, and as in the procedure, right click on the image, select "copy image location".
That (image location) of that image (the group's headshot) would be:
http://images.makulitrepublic.multiply.com/logo/3. This is also the URL of the image we want to embed.
NOTE: The image location is also its URL.
now, in the code <img src=IMAGE_URL> , replace IMAGE_URL with the URL of the image we wanted (the group's headshot).
that would turnout as:<img src=
http://images.makulitrepublic.multiply.com/logo/3>when you post this on a guestbook, here's how it will turnout:

* read it over and over, im sure it's easy when you get tp try it! =D
Tutorial on Changing Background Images on POSTS:
http://makulitrepublic.multiply.com/journal/item/22