Well I was thinking about redirecting all invalid users (such as spammers) depending on their referrals to a dummy page showing only ads. Is that legal? Well that get me banned from adsense or even google?
Read the terms of service and you will see it is. Also you are cloaking to a point as googlebot will see one thing, but other user agents will see a totally different page. Thin ice I would say.
I wouldn't try that with Adsense to tell you the truth. And how exactly would you be redirecting "spammers" from where they come from?
Well I am trying to block users who come from warez sites and I already have the list of warez site that are pointing to me and I am getting a lot of referrals from them, so I am block all users coming from warez site, but I was thinking to take it to a next level and put some ads for them!
Why in the world would you do so? It seems you have a password recover program, they can be infact potencial customers regardless of coming from a warez site. If a cracked version doesn't exsist of your software you have a HUGE potencial they will convert.
INV, the warez site contains a crack of my software and it makes my program work fully, so no they are not potential customers and I don't want them to download the software from my site.
You don't want to piss those guys off. Though I guess they already screwed you over so you don't have that much to lose. Drop Google an email and explain the situation fully and ask them?
How about redirecting them to one of the proggies that take any traffic, even if it only makes a penny a click? Might not be a ton, but not losing your software then, making a few bucks, etc.