Here's what is probably happening. If you just copy/paste some text and pics from a site - the photos will show up. However, a lot of servers monitor outside people linking to their images (tripod especially) and will replace the image with a blank or just a logo.
The best way to post an image is as follows.
Get an actual copy of the image (right click - save as...this works 90% of the time) to your hard drive.
Go to
www.imageshack.us and upload the image. They'll give you a weird link (a bunch of links actually - choose the very last one)
Use that link to post the image in here using the yellow picture button above your text box.
This will host your image for more than long enough.
Good luck.
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