David, you should be able to create an interesting moment when leads view key web pages. In Sales Insight, your sales team can choose to subscribe to be notified of every interesting moment like this one, within the lead feed.
More info on lead feed: https://community.marketo.com/MarketoArticle?id=kA050000000Kywp
Alternatively, you can send alerts to lead owners when leads view these pages. I'd recommend the first approach, however, because they will have more control over the emails they receive, and will be less likely to filter out all Marketo emails from their inbox.