This is an old revision of the document!
OK, so you don't have much time?
here is the gist of it :
use the firefox-add-on :
https://addons.mozilla.org/en-US/firefox/addon/b-dns/
visit the search engine:
http://grep.geek/
use the openNIC proxy :
http://proxy.opennic.org/
need a faster wiki than this? use the fossil wiki:
t.b.a.
which TLD has the most subdomains?
http://report.opennic.org/ see TLD info from menu