I bought around 5000 one-way links from "one of those companies" They said they would link to my site gradually during 3 months to avoid problems but did it in one instead. I stopped receiving trafic from google a week ago. Now SR for my keywords can be found in the very end. I see they did penalize me! This "company" did not reply to my message. Does anybody know if i could resolve this with google? I know i should wriet to them but what if this was not the issue?

Gee, you bought 5000 links which is clearly against Google's terms of service. What did you expect?

You tried to fool Google, but you were fooled by the xyz company.
You must know those links must not be from relevant site and they are of no use and if you get them in short there are great chances you will get ban.
Try to make re-inclusion request stating the truth.

( or you may play one more trick : get all the links on a single page and using robots.txt prevent that page from crawling. ) I don’t know this will work or not

I think i should wait for a while! As a matter of a fact 90% of my site went into supplemental r. This could be the case to resolve easier, i hope again... Otherwise I got yahoo and msn on my side, 1-2nd positions that barely cover 1% of what google's hits.((((

Submit a re inclusion request and maybe someone will look at it. OR change domains....

well all i can say ....you may just have to start all over which is going to take its own sweet time. Well I hope you have not spent a bomb on the 5000 link back

Our team worked on this site for two years, we have acheaved good results, now one mistake commited before the new google policies... All the team gets fired!!!!!!!!!!

Actually that's a very old Google policy. They've always warned webmasters not to try to manipulate their SERPs.

Dear Sir
can you stop admiring and defending google 50 times a day... You have 1230 posts, it looks like it's your job.... I can advertize my site to as many sites as i want, it is marketing, put banners and text links.. Since when it should be considered "cheating"

My post count just means I participate in this community a lot. It doesn't mean I have made 1230 posts defending Google. In fact I have a website that performs very poorly in Google and I am not happy about it. But instead of whining about it and blaming Google for anything I can I am instead working hard on improving my site with the hopes that it will improve in Google's SERPs.

And you are free to market your website any way you want to. And Google can choose to run their search engine how they want to. They don't owe you anything. Especially when your attitude is that they do owe everything and you knowingly try to violate their rules. You knew what you did was wrong and got what you deserved. Learn from it and move on.