Everything is searchable, unless someone questioned it previously, answers on Stackexchange network matters because they are answered by professionals and accepted by community.
The site is in Beta and we are building a solid database of good questions and answers, not the general or basic ones.
Users can find information at various personal blogs or sites but what matters is authenticity of the content they share on their sites as there is no one to review their content. I will provide you one example for this :
Was Lord Rama a non-vegetarian?
Now in the above question, the site which is referenced by the user who asked the question translated wrongly, and hence, provides false information to his visitors, whereas on Stackexchange, we have other users to review the answers by upvoting the good ones, and down voting the wrong ones which helps other users to refer a genuine answer.
Not only that, some users also provide secondary solution/version answer, which is useful as not all websites cover different versions of answers, so....
Should I search on Internet before asking question? - Yes, do it if your query is basic or it is too broad, or you have skeptical questions like whether this is true or not etc types.
But if your question is interesting, unanswered by search, you think may be helpful to others if I post it here, than ask, nothings wrong in asking a question which is searchable online, so that users get authentic information from this site.