Maggie's doesn't have a 'Contact' page for a couple of reasons. For starters, most of the gang are working professionals and simply don't have the time to respond to individual inquiries. Then there's the hours needed to sweep out the stalls and slop the hogs that has to be accounted for. And, to be honest, we're kind of a laid-back bunch and aren't very concerned about typos and broken links and whatnot, which is really what a contact page is for. If all you want to do is mouth off about the article, that's why there's a comments section.
By the same token, we always appreciate suggestions for posts and links to interesting things, so we don't consider it 'off-topic' or 'threadjacking' to leave them in the comments.
Whose thread you leave it in would depend on the topic. If it's a newsy item, then the daily links would probably be the best spot. If it's a more worldly item, especially if it relates to the military, then Bruce is your guy. For cultural matters, such as education and the economy, I'd turn it over to Barrie. Dr. Bliss, our resident shrink, doesn't have the time to spend with comments, so don't bother there. Geek stuff and videos and such should be directed to me, Dr. Mercury.
As a small caveat, many times a blogger will glance over the comments ten or twenty minutes later, but then get busy and not check again. So if you leave a suggestion and it goes unanswered, it might just be the person never saw it. If it's actually important, leave it in one of my threads because I answer everybody. (I work at home so I have more time than they do)
In summation, none of the bloggers are going to complain if you jump into one of their posts with an off-topic link. Proper protocol merely dictates that you acknowledge your off-topicness with a quick "Pardon my being off-topic, but have you seen this amazing video?" or words to that effect, just to let people know.