Music is available in various formats in many places..ultimately YOU will have to decide about some of them, depending on the uses you intend. There are many totally legal sources posted here at various times.....though maybe not always exactly what you may be looking for.

Some groups and artists post small samples of their work....some folks post older stuff that is not a problem. In other places, like 'newsgroups' it is a mix of legal, illegal and borderline..(like a 20 year old album that may still be 'owned' by someone, but looks like it is never going to be released to CD. A lot of folk music, especially the older stuff, is not actively traded and 'stolen'....but artists still need to make a living from their current work, and would not appreciate new releases being pirated.

If you are going to assemble copies of other's work and make and sell CDs for your own profit, it is clearly wrong....if you are just planning to listen to a song that you always wondered about, and maybe don't intend to 'keep', it gets harder to categorize.

I often look at the binary 'newsgroups' to see what is there, and use my own judgement about whether to download it. To do this I simply use a newsreader like Agent.....(if you don't have access to newsgroups, and don't have broadband access, you are very limited anyway) There are some special programs designed just to download 'binaries'...that is, music, pictures, videos...etc..but you need to know which ones you need for different applications.

Not a short answer, is it?.....Sorry, but there just IS no short answer to the question.