Can I use the name of a famous folk/rock singer as a pseudonym?

Only if you don't in any way attempt to pass of your work as their work.

For instance, Tom Kruz inventor of the hover round or Mark Wahlberg of the Antique Roadshow have every right to use the same name, but they can't be advertised as them in a movie.

Do you mean, can you call yourself by the singer's name for any purpose - such as publishing a book? No, I don't think you can.

Yes, but expect to be hit with a lawsuit as soon as you publish.

I would imagine not. You'd probably get sued. You should use something like ''John Smith''.

Simples...

yes