My experience tells me that they usually are the first search result in google -- and when they aren't, I specifically look for them in the search results because the site is incredibly accurate and useful and I have come to trust it.
Just as a side note, please make sure to upvote both the question and any helpful answers if you've found the question using Google and it helped you as that's how Stackoverflow dynamics work.
It seems like very few people understand that it doesn't cost anything to upvote other answers and especially questions. Lots of good questions get around 0-2 votes, but clearly draw significant activity and interest otherwise. Are people afraid of point inflation?
They've also recently created a Gold "Electorate" badge, which is defined as "Voted on 600 questions and 25% or more of total votes are on questions." This should encourage people to vote up good questions as well as good answers.
I feel that since there are comments, answering a question should automatically upvote it. It depends on what the criteria for upvoting a question is - whether it's "not spam/trash or poorly worded" then this would work, I feel most people go on "it taught me something amazing/unique" however.
The problem is that it isn't clear WHY you should upvote a question.
Upvoting an answer is helpful - I'm saying that I confirm that it's correct and you should believe it - but upvoting a question is just gold star time.
On a funny note: I wonder how many of those questions were answerable by the first result of a simple google search? :P