Re: how to block-out backlinks ?

Links on your site going to other sites
or
links from other sites going to your site?

The first you can "disable" with various techniques, add a
redirector-page, use javascript instead of a link, etc. The later you
can only "block" by having the other webmaster remove them for you.

However, I don't think you will get any sort of penalty on the basis of
sites pointing TO you, since that would be way too easy to use against
other sites (eg webmaster of site A adds website B to lots of
bad-neighborhood-sites)... If Google doesn't value the other sites,
then they just don't count as backlinks.

Cheers
John