The ABC doesn't offer a facility to search the forums which is sometimes a pain. As an addition to the TechTalk Wiki the TechTalk Forum Search has also been created. This search facility adds new posts to the index twice a day and will soon index every post accessible (and some that aren't) in the TechTalk Forum.
Unfortunately if you're trying to search the other ABC forums we are still left with Google as the best option. Kevin has created a good custom interface for Google which makes it easy to search the ABC Forums.