What are you seeing exactly? Do you see the broken image placeholder (the "red x" in IE) where the image should be, or is the space completely void of any image indication. Keep in mind that Mozilla Firefox simply hides the space where broken images sit, so you won't see anything there.
First thing I would do is
get Firefox. If that step is done, go get
Web Developer and
Firebug. I find both of these tools absolutely invaluable for any kind of web page troubleshooting.
In this case, open one of the broken pages, then got to the web developer toolbar and choose Images > Find Broken Images. See what it finds and go from there.