Search doesn't always work that well. Results can include replies to posts that are not all that helpful and as posts age they can become harder to find. Add the aging of posts on older topics and it's easy to loose a good thread on an important topic. Unless you know who posted it or what exactly was said.
The tags can help but there are lots of threads here yet to be tagged.
I vote for not posting to a thread if all you intend to do is say "try searching". But hey, maybe that's just me.
Thanks for the OP bigjohn. I'm just starting to play with ubuntu and that does look like it will come in handy. I book marked it for later.