OK ...
Now I'm confsude.
On the one hand, you're saying ...
nice work, these sobs have decided swap my photo for another photographers image but they still have my image on their system.
not even an email for these ppl.
Then you go on and say ...
how do i find out the webmaster?
when i orginally posted my email to them it got changed very quickly <5hours
A few things here simply do not gel.
Ok, they've swapped out your photo for another; clearly you've alerted them to the fact that your photo was used without permission, and they've now corrected the situation, but how did they find out that they were using it without your permission?
Read on ...
You say "When you originally posted" your email? To them? But you say that there's "not even an email for these ppl". With no email address for them, how did you send them an email?
It seems that you have this information and have used it; otherwise how could they have acted and removed the image so quickly?
You also say "but they still have my image on their system.".
How do you know this? Do you have access to their system? Do you you know someone who works there?
Given that you're saying that they're a garage, I'm surprised that this action occurred so quickly. My experience is that most businesses are not very web savvy, and certainly, checking of emails is often a low priority.
Acting upon them is an even lower one.
Please don't think I'm coming down hard on you; I just don't understand the full situation here, and some of what you've said seems to be quite contradictory.
The bottom line, were I in your shoes, would be that they have now rectified the problem.
While this may be the second occurrence, I would probably be inclined to let it rest there, but should it occur again, I would first of all take a dump of their website (so you have evidence) and then issue them with an invoice, along with a copy of any of your prior correspondence in the matter.
You are keeping copies, right?