Questions, corrections, advertising or data: there is one address for all of it.
Email: hello@rustheatmap.org
A server looks wrong: Most of what appears on a server page comes from what the server itself publishes: its name, description, tags, wipe schedule and header image. Change those at the source and the page follows within five minutes. If a wipe was missed or a value stays wrong after that, email the server's address as ip:port and say what you expected to see.
Advertising: The advertising page lists what is available. Email with what you have in mind.
Using the data: You are free to use the figures on the site in a project. Ask first, and we can point you at a better route than scraping pages. For the data behind a single server, see the server list.