Well, first upload your pictures to a web server, then simply link to them using the image URL, like this: <font class="small">Code:</font><hr /><pre>[image]http://host/picture.jpg[/image]</pre><hr />
or whatever. The hard part is finding a server to host your pictures. Do a google on "image hosting" and you should find servers willing to take your pictures. But like I said, since you need a server anyway, I have a server and am willing to host your pics for now until you get another account set up at imagestation or wherever.
Also, I think if you register in the media section of this site, you can upload your pictures and then link from there.
Edit: Before you upload your pictures, make sure they are properly encoded and compressed. Resize them if necessary to about 1024x768 at most, preferably 800x600. Adjust the compression until you get them down to ~30k or 40k. You can put a link in your thread to the higher resolution and quality images for those who want a better look.