George, I'm not sure how Fotki works, but if you have your photos in a photobucket album, all you have to do is click on the last line of text below the photo (it's labeled "IMG code"). By clicking on it, you have just automaticaly "copied" that text.
Now go to your MCM post window, and simply "paste" (Control + V on a PC, apple key + V on a Mac) that copied text into your window.
In your message window you should now see a line of gobbledygook that begins with [ IMG] and ends with [ /IMG]. It'll look something like this:
[ img]http://i82.photobucket.com/albums/j269/harrypri/misc/photobucket.jpg[ /img]
That's your photo's "address" in computer lingo. That string of text tells the computer where the photo you want to post is located (in this case, on the photobucket site). While you're still looking in your post window, you'll see that line of text, but when you click the "submit" button, that line of text is telling the computer where to find that photo... and the photo will be displayed as an image in your posted message. If the photo does not appear in your posted message, the photo's "address" was not copied and/or pasted correctly. In that case go back and try the "copy/paste" thing again.
It sounds complicated in words, but once you get the hang of it you'll see it's incredibly easy.