Hey, that's great news! I can't remember anyone ever posting that they can't find signs. Either your city officials are more active than most, there are other sharks in your area, or there just aren't any spammers. Whatever the reason, keep your fingers crossed.
I can't speak for other parts of the county, but the southeastern quadrant seems particularly infested with spam. The Galesburg/Scotts area has been particularly hard hit in the past week or two. I'm hoping to make a sign collection run in the next few days.