Well, its happened first time with me that someone is copying my posts and posting it to his/her blog. Its frustrating. How should someone contact to other s\admins for this issue? And if the reply is not positive, what then?
It isn't worth your time trying to get them to take down the content to be honest. Most of those who would be 'using' your content in the first place aren't the types of individuals that necessarily care to help you out. While frustrating, it is going to happen regardless. Take pride in the fact that someone wants your content, and move on.
1) Quickly scan the site for any "about us" or "contact us" pages. A contact email address can usually be found here. 2) Send a friendly message asking for your content to be removed. 3) Send the website owner / webhost a DMCA notice for your content. 4) Pursue the matter in a civil court that has proper jurisdiction. That said, I am in favor of brandon93s' concept of just letting go. In fact, I would sent the site a thank you email with a note asking to be attributed on the copied content as the author.
I'm with Leo... In fact, sometimes (provided that the website isn't a scam, in which case I handle things differently) I can get a back link out of the issue.