I usually buy domain names when I think of something cool and it is available. (ilovetotsinpdx.com anyone?). The easiest way to find domains the "Web 2.0" way is using this cool AJAX’y interface to search open domains.

http://instantdomainsearch.com

Makes it fun and easy! BTW I do use http://www.active-domain.com for my DNS/domain registrar and I use http://hostmysite.com for all my hosting. Why? Just because I found it easiest :)