Why bother to learn more about logic and arguments? Does it really matter and does it really help anyone? As a matter of fact, yes it does - and there are several good reasons to take the time to learn more about both topics.
The most immediate and obvious benefit from such a study is that it can allow you to improve the quality of the arguments you use. When you create logically unsound arguments, you are much less likely to convince people that you have a valid point to make, or get them to agree with you. Even if they aren't familiar with logic, many people will realize that there is something wrong with some fallacious arguments without being able to identify the fallacy involved.
A second and closely related benefit will be an improved ability to evaluate the arguments of others. When you understand how arguments are supposed to be constructed and also how they shouldn't be constructed, you will find all sorts of bad arguments out there. You may even be surprised to find out how many people are swayed by bad arguments.
Although you may not realize it immediately, there are arguments all around us vying for our attention and acceptance. We hear arguments that we should buy car A rather than car B. We hear arguments that we should vote for politician Smith rather than for politician Jones. We hear arguments that we should adopt this social policy rather than that social policy.
In all of these cases, people are making or should be making arguments - and because they are trying to get you to believe their conclusions, you have to be able to evaluate those arguments. If you can demonstrate that an argument is sound and valid, not only do you have reason to accept it, but you can also defend this acceptance whenever someone asks you why you have done it.
But when you can identify bad arguments, it will be easier for you to free yourself from beliefs which are not well founded. It also allows you to challenge people making claims which you think are suspect, but you would otherwise have difficulty in explaining why. That won't always be easy, because we often have a heavy emotional and psychological investment in some beliefs, regardless of their validity. Still, having such tools at your disposal can only aid you in this process.
Unfortunately, the argument that prevails is usually the one which gets said loudest and last, regardless of its actual validity. When it appeals to people's emotions, it can even have a better chance of looking superior. But you shouldn't allow others to fool you into believing their claims just because they were persistent - you need to be able to challenge and question their assertions.
A further benefit will also hopefully be an ability to communicate more clearly and effectively. Muddled writing tends to come from muddled thinking, and that in turn tends to come from a poor understanding of what a person is trying to convey and why. But when you know how an argument should and should not be presented, it will be easier to un-muddle those ideas and reform them into a stronger pattern.
And while this may be a site dealing with atheism, it is also a site which deals with skepticism - and not just skepticism about religion. Skeptical inquiry about all topics requires an ability to use logic and argumentation effectively. You will have good cause to use such skills when it comes to the claims made by politicians and advertisers, not just religion, because people in those professions commit logical errors and fallacies on a regular basis.
Of course, simply explaining the ideas behind logic and arguments isn't enough - you need to see and work with actual instances of the fallacies. That's why this FAQ is filled with numerous examples of everything described. It is important to remember that clear, logical writing is only something that will come with practice. The more you read and the more you write, the better you will get - this isn't a skill that you can acquire passively.
This site's forum is a good place where you can get such practice. Not all of the writing there is of the highest caliber, of course, and not all of the topics will be interesting or good. But over time, you will see some very good argumentation on a wide variety of topics. By reading and participating, you will have the opportunity to learn quite a lot. Even some of the best posters there will readily acknowledge that their time in the forum has improved their abilities to think and write on these issues.