System Admin For A Growing Site.

We're seeking a dedicated person to work just for us, somone good at system monitoring and Server software. we're running our site on IIS, Windows Server 2003. We would like someone who will be able to MAKE SURE our systems are up 24/7, react within the MINUTE to any emergency be available on chat almost 24/7, be our inhouse advisor on issues like load balancing, when we need it, why we need it, inform us about server capacity in terms of how many hits it can handle or how many sites can be hosted on it, updating patches, making sur ethe latest in software and security protection is installed, etc, etc... Someone with proven track record, even possibly somone who's worked for a hosting or collocation company before. This is for a long term relatinoship, so watch your bidding please. Thank You