Tool for searching images

I've been looking for a tool that would search for picture's origins in the internet. If I have a picture on my computer and want to find out where is this picture from. What could I do, except asking ppl or trying to guess keywords in google? Is there a tool which could help me?

Damn! I was looking on "Last updated: Sat Jan 31 22:46:41 2004" and confused 2004 with 2005 :(
Sorry!
That leaves me to the one and only choice: full research of image searching as part of my studies. I will post here the results (good or bad).