Here is a list of PuTTY web site mirrors. I add to this list when people tell me mirrors exist: I don't go out looking for them. If you want to mirror the PuTTY site, you're welcome to - tell me about it and I'll put it on the list.
The official PuTTY home site, in case that isn't where you're reading this, is
Mirrors of the whole site exist at:
Be aware that the mirrors are not updated instantly. Also, none of the FTP links on the Download page have been mirrored - they still point to the same places as on the original web site. (The HTTP links on the Download page have been mirrored.)