A common example is the "false generalization," in which people argue that because some people of a given group are known for certain behaviors, that this is true for all members of the group. This is similar to the fallacy of “guilt by association,” where someone is accused of believing and behaving like those with whom they have collaborated in some previous and maybe random way.
Another common fallacy is “two wrongs make a right,” making the case that because someone else or some other group is doing something reprehensible, that what I or we are doing is justifiable or is not so bad.
Then, of course, a favorite one is the "ad hominem" argument, where we attack the bearer of the message as a bad person, then insist that nothing that person says is worth hearing or believing.
Not only does the use of such logical fallacies abound in opinion pieces and on editorial pages, we use them in our personal relationships and in our endless arguments with our co-workers, friends and family members.
The truth is our friend. Let’s make sure we make every effort to speak the truth, the whole truth and nothing but the truth, and always in a spirit of care and respect.
Here's a helpful link to Labossiere's complete list of 42 logical fallacies, complete with explanations and examples. You can feel free to refer to it to point out whenever I'm inadvertently guilty of employing some them myself.