How do you copyright songs?
Copyright is free and automatic, starting from the instant your song is fixed in any tangible form, such as notes on paper, sounds on tape, or a digital record in a computer.
You may optionally register your claim of authorship under the laws of a few countries, but the USA only requires registration if you are going to sue in federal court.
If you buy songs legally from the LimeWire store then it will cost money. If you are caught downloading songs illegally without paying for them then it could cost you a lot of money. To quote LimeWire: What Happens If I Commit Copyright Infringement? Your activities on peer-to-peer networks such as LimeWire may be monitored by copyright owners. Violation of copyright laws may subject one to substantial money damages. Copyright owners have sued thousands of…