So, here are some highlights of the material from the link (bold and italics are mine):
WHAT WORKS ARE PROTECTED?
Copyright protects "original works of authorship" that are fixed in a tangible form of expression. The fixation need not be directly perceptible so long as it may be communicated with the aid of a machine or device. Copyrightable works include the following categories:
(1) literary works;
(2) musical works, including any accompanying words
(3) dramatic works, including any accompanying music
(4) pantomimes and choreographic works
(5) pictorial, graphic, and sculptural works
(6) motion pictures and other audiovisual works
(7) sound recordings
(8) architectural works
HOW TO SECURE A COPYRIGHT
Copyright Secured Automatically upon Creation
The way in which copyright protection is secured is frequently misunderstood. No publication or registration or other action in the Copyright Office is required to secure copyright. (See following Note.) There are, however, certain definite advantages to registration. See "Copyright Registration."
Copyright is secured automatically when the work is created, and a work is "created" when it is fixed in a copy or phonorecord for the first time. "Copies" are material objects from which a work can be read or visually perceived either directly or with the aid of a machine or device, such as books, manuscripts, sheet music, film, videotape, or microfilm. "Phonorecords" are material objects embodying fixations of sounds (excluding, by statutory definition, motion picture soundtracks), such as cassette tapes, CDs, or LPs. Thus, for example, a song (the "work") can be fixed in sheet music (" copies") or in phonograph disks (" phonorecords"), or both.
MANDATORY DEPOSIT FOR WORKS PUBLISHED IN THE UNITED STATES
Although a copyright registration is not required, the Copyright Act establishes a mandatory deposit requirement for works published in the United States. See the definition of "publication." In general, the owner of copyright or the owner of the exclusive right of publication in the work has a legal obligation to deposit in the Copyright Office, within 3 months of publication in the United States, two copies (or in the case of sound recordings, two phonorecords) for the use of the Library of Congress. Failure to make the deposit can result in fines and other penalties but does not affect copyright protection.
INTERNATIONAL COPYRIGHT PROTECTION
There is no such thing as an "international copyright" that will automatically protect an author's writings throughout the entire world. Protection against unauthorized use in a particular country depends, basically, on the national laws of that country. However, most countries do offer protection to foreign works under certain conditions, and these conditions have been greatly simplified by international copyright treaties and conventions. For further information and a list of countries that maintain copyright relations with the United States, request Circular 38a, "International Copyright Relations of the United States."
So, basically, you don't need to register or anything, just by recording it on some sort of medium (in this case, the computer hard disk) you have created a work, which is unpublished, and is thus protected under US law. However, the preceding paragraph would make it seem that copyright infringement is possible internationally. Thus, given the international nature of the web, unless the plagiarist is a Yankee like yourself, you're probably helpless if someone from a country that does not offer protection to foreign works steals your songs. Actually, come to think of it, a lot of hit Asian songs are just reworkings of American music.
Also, notice that if you publish a work, that is, make a recording and then lend, rent or sell the CD or MP3, you are bound by law to send it to the Copyright Office within 3 months of publication. I doubt that most amateur musicians bother to do this, though.
Hope you were able to sift through this huge post.
see you on the dark side of the moon
