Next time something like this happens you can either record and demo and request a ban on the Request Ban thread or you can type "&there is a hacker on dust 2 please help" or something like that and it will send a message to every admin currently on the cs:s and cs:go servers.
Taz, along with the suggestions the other admins have posted, you should look into joining Teamspeak. Even if you cannot use the voice chat, it is the fastest and most effective way to reach out to admins and get immediate help on the server.