if you post them directly on this site, the ff forums, then they'll be here when a remote site may change or go down and you lose the images. thus, i'd recommend posting them here. normal file types are allowed, like jpg, png, bmp and maybe a few others and there's a limit of 250k max file size, which is good for a fairly decent representation if the image size isnt too large.
but, if you insist on a remote site, i'd use imageshack. free, can use up to a meg file size, i think, and they're not likely to be going down any time soon.
If wishes were horses... there'd be a whole lot of horse crap to clean up!
Craig