Yes, you have to upload them to the 'Net. You can't post them directly off your own harddrive. You can click on the "Photo Gallery" link to the left and create your personal gallery right here. Follow the directions to upload.

When you get a picture uploaded:
--View it
--Right click on it
--Select "Properties"
--Highlight and Copy the URL

Come back to the forum and open up a new topic...
--click on the [img ] tag one time
--Paste your copied URL immediately after the tag
--click on the [/img ] tag once more
--submit the post

Ta Da!
Hope this helps!