sorry, may not be right forum to ask, but i want to post a pic of my car in reply to another member's post... how do i attach an image from photos stored on my computer?

 

You need to store the photo on a 3rd party photo facility like Webshots or Imagestation. Some charge a fee, some don't. Or you can buy a membership here and get a HUGE photo album which you can post pictures from in your posts.
If you use an outside photo facility, you'll need to use "image" tags to link those photos into your post. Go to the site FAQs to see exactly what I mean by "image tags".