Format for a url that goes to Google image search?

1. url: https://www.google.com/search?tbm=isch&q=findSomeImage,
2. Nothing official that I’m aware of, but this blog has some documentation.
3. Nope, no limit you should worry about if you’re manually clicking the urls. (I’m sure google has some kind of flood protection against bots, though)

So, the only change you have to make, is to add the tbm=isch option to your urls.