You mean, people are scraping Google Groups (any group in particular?) for content and publishing on their own sites? I didn't know that - it's hard to guarantee your content is going to get syndicated (and the backlinks preserved). I have found submitting press releases at PRlog (in popular niches) often results in lots of syndication - including in Google News results, although I have had mixed results with that, my last PR only got syndicated on one other site which was a bummer...

you can also syndicate all your post via rss feeds.. other sites also scrape these as well so its free backs links to your site as well..

where to make posts which will be automatically syndicated( re-duplicated on other sites )?

for instance if to make 1 post on google group, it will be automatically re-published on other forums

what other places like google group do you know?