Oooh! Something I can actually contribute to with a measure of authority.
LOL.
To be blunt, you could take a semester long course on copyrights at your local university or law school and even if you were also there to complete your Juris Doctorate you wouldn't know all there is to know about copyrights until you practiced law in the field of copyrights for several years... and even then you would only know most of it.
And any post I make here on the subject would be long and confusing and most of you wouldn't read it.
Here are two resources, if you are really interested in the subject that might give you a basic (very basic) overview and if, upon reading these you have any questions about what you have read or something that wasn't covered I'll do my best to answer them.
http://www.copyright.gov/help/faq/ - FAQ from the Government Copyright Office.
http://en.wikipedia.org/wiki/Copyright - Good ol Wikipedia where the truth or lies may be found. Read at your own risk.
Also Alectric that symbol you made with the parenthesis (c) is not a copyright symbol and I doubt it would be recognized as one legally. But as I'll point out in a moment it's really a moot point.
Trevor that link to all the secrets of my keyboard is FRICKING AWESOME! I've known you how long and you are just sharing this treasure trove with me? What else do you know? Do you know where Atlantis is? The lost books from the Library at Alexandria? Are you holding out on me? So awesome. And so bookmarked.
There is something called a "Poor man's Copyright" which, back when I was in a band we used to use. We would seal documents up and ups, fedex or mail them back to ourselves, family or lawyer for safe keeping. As long as they remain sealed you can admit them in court as proof your work existed before the creation of someone who is either suing you for infringement or you are suing for infringing your rights.
But the answer to almost all your questions and the subsequent responses is found in these two FAQ entries from the Government site I linked above:
When is my work protected?
Your work is under copyright protection the moment it is created and fixed in a tangible form that it is perceptible either directly or with the aid of a machine or device.
Do I have to register with your office to be protected?
No. In general, registration is voluntary. Copyright exists from the moment the work is created. You will have to register, however, if you wish to bring a lawsuit for infringement of a U.S. work. See Circular 1, Copyright Basics, section “Copyright Registration.”
Defending your copyright zealously is really the key to remaining copyrighted. You can lose it if you don't attack those who try and usurp it. But as stated in the quote above you cannot sue someone without registering the copyright. So while your copyright is supposedly yours as soon as you create and present your work you cannot defend it without registering which can leave you in a pickle if you don't have other things like dates and signatures documented (thus my advocacy for the poor mans copyright).
As far as the sprites and using others logos and images thing. That brings in things like fair use, satire and parody. I'm don't know if you are familiar with the webcomic "VG Cats" but Scott Ransoomir and I have had a couple discussions about why he hasn't been sued yet. If you see the T-Shirts he sells you will be surprised to find how many Pokemon, anime and video game characters he references in his drawings and jokes on the shirts he sells for profit. I told him the last time I saw him I couldn't believe he hadn't received a "cease and desist" letter from Nintendo yet.
A lot of people talk about fair use, satire and parody as if they are armor they can wear to protect themselves from things like copyright infringement, slander, libel, loss of income from work product and anything else copyright holders than throw at someone. Satire, Fair use, and Parody are in fact not a protection from these charges. They are what is known as an "affirmative defense."
A common example of an affirmative defense is "Self Defense" or "Not Guilty by Reason of Insanity."
In court, even in civil court the defense is innocent until proven guilty and it is the burden of the plaintiff (or the prosecution in criminal cases) to prove the injury (prove the lost income, damage to reputation, whatever... and this brings up something interesting in these kinds of cases... in that a judgement for the plaintiff can sometimes result in a victory in name only because even if they can prove you violated their copyright if they cannot show some tangible damage to their reputation or financial loss they will win but be awarded very little, if any money). But an affirmative defense stipulates to the charges of the plaintiff (agrees that what the plaintiff is saying about the defendant using his copyright is true) and shifts the burden of proof to the defendant that the use of said items is legally permitted by Fair Use, Parody or Satire.
And that can be difficult and you usually need a pretty good lawyer to pull it off. Which is why when most folks get a cease and desist letter they consult a lawyer and then fold like a card table.
Which is also why sending a cease and desist letter can be very useful and necessary in defending your copyright. But before you send any letter threatening legal action you want to make sure that a) you can and will follow through with the threatened course of action and b) aren't overstepping the bounds of what you are threatening.
You wouldn't for example, want to tell someone to stop using one of the characters from your comic on their T-Shirts or you will come over to their house and and kick their asses. You wouldn't want to threaten have them arrested either. You don't have the authority. And even if you feel you are due a cut of the money they are making from selling shirts with your character on them you can't say "and I'm going to sue you and take your house and car!"
You want to keep everything businesslike and use professional terms like "if you do not cease the use of our copyrighted images SSS Corporation will have no recourse but to seek legal enforcement of our copyright as well as seek legal remuneration for damage to our property, lost income and associated legal costs."
Anyway, I hope that clears up a thing or two.
Maybe I should write an article on the subject.
