do music artis buy their own albuns to help sales or to help generate
a buzz for themselves?

I've been in the music business for over 50 years and have never heard
of the practice.  First of all it would be counter-effective since
artists only receive a small percentage of the actual selling price. 
You could spend a fortune and the sales would never have an effect on
the national chart position.  There are a thousand other ways to
create a "buzz" for yourself, and buying your own records is not one
of them.

Given the amounts you have to buy in order to even create some kind of
buzz, it is highly unlikely.

that would be dumb.

I doubt they do that.

however, most recording contracts force artists to buy their own CD
from the studio to sell at concerts.  and not as cheap as you'd think.
 The price artists pay for their own CD is close to $11 per CD

Two words - "White Lion"