Here's an article from Great Schools with some college planning advice from a mom whose sons both got into good schools. One point I noticed was her advice to start visiting colleges right after 8th grade, which is earlier than I've heard from other sources, but seems like a good idea. She also recommends sampling different campuses from all over the country, so the kids get an idea of the kind of vibe they're looking for. Here's the link:
http://www.greatschools.org/college-prep/planning/580-one-moms-timeline.gs?page=1