First you will most probably want this to run as a service(s). Win32::Daemon or Win32::Daemon::Simple will help you with this.

Win32::Service will tell you if a service is running, Win32::FileOp::GetDiskFreeSpace() will tell you how much free space is on a disk drive, so will Win32::AdminMisc, Win32::IProc (installable with PPM from http://jenda.krynicky.cz/perl) will give you information about processes. I don't know what do you mean by "system health" though.

As far as the SMSs are concerned, I believe this depends on your cell phone operator. I send them via SMTP. (Though it seems I'll have to change the operator since the (censored) Eurotel started including adds in the SMSes so I can only use 60 chars:-(

Jenda
Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
   -- Rick Osborne

Edit by castaway: Closed small tag in signature