i've noticed several IP addresses accessing my site and downloading my images, how cna I provent this happening? We know this happens as our unique product has been copied by several people before.
Sorry, but you really can't. You could disable browsing of your /images folder, and that might help a little, but you'll want to leave it accessible in your robots.txt file so that you reap the benefits of a google image search. You could disable right-clicking, but that's kinda humorous to me considering I can click 'Print Screen' and paste the image to any paint program I own. Even if you could disable the Print Screen button, there are freeware screencap programs that would enable people to do the same thing. I suppose if you did all of the above you'd eliminate 90% of image theft, at least from the less computer-literate people. But then again the people who are stealing your images are probably using them in a web-based way, which would make them computer literate. Unfortunately, by putting your work on the internet you're exposing it to be copied... whether it's morally right or wrong doesn't matter, it's gonna happen anyway.
You can't protect your images from being downloaded. About the only thing you can do is add a watermark. I've written a very simple script that will automatically add watermarks on images. It's called Automark and can be downloaded for free here: Automark v1.1
Use htaccess to block blank refers and hotlinks. here's the code NOTE: Make sure the image "warningimage.jpg" is is the root and its not hotlink protected or your server can go into an endless loop.
You do realize that by people simply looking at your webpage they are downloading the images in their browser catch right? If you don't want this happening don't put your pictures online.