Outlook on plagiarism

Good Morning,
Plagiarism is a very intimidating word. I understand that we need to give credit where credit is due. I would not want someone to use something that I have written and lead people to believe that he or she had completed the work when it was I that had done it all. It is a form of theft and not acceptable. I have to keep my book open to the APA formatting when I try to reference a article or journal. Sometimes I struggle with trying to figure out what a paper is that I am reading such as, journal, article, newspaper and then if I am not sure then how can I cite it and reference it correctly? If I was aware of someone using my work and not giving me credit the first thing I would do would be approach that person and ask him or her why she had stolen my work and not given me credit. I would expect them to retract or put a correction in their paper, if not then I would bring it to the attention of someone, either their boss or teacher. Last term when I was taking Compostion I and was just learning about the APA formatting and the word plagiarism there was a journalist and I do not remember his name had been accused of plagiarizing and I heard it on the news. I am not sure what happened to him with his job but I know that he was publicly embarrassed. You look around and since I learned this word I realized that if you put a quote at the end of your emails and do not list the author of that quote then you are not giving them credit and that is plagiarism. You can look at facebook and see alot of quotes in different pages and not an author listed, you tend to look at things differently since I started at Kaplan.
Does the internet blur the line "legally owned"? I would have to say yes they do because if you post something for the world to see you have really lost the ability to control what happens to it.
I hope you have a great day!
Deb