Help me find an Uninterruptable Power Supply, Please!?

Can anyone recommend some UPS brands & models that would suit my needs, I have been searching websites and not really coming up with the information I am looking for, asking the supplier or manufacturer seems to be pointless as they want to recommend whatever they have in stock or want to get rid of!

My system uses about 200w normally and is pretty much maxed out at 300w if I load up everthing I can at once. (I still want to leave some room for any possible future expansion without going completely overboard) I am using 'Windows 7 Professional' 64bit and would like something with

1.Surge and lightning protection.

2.Voltage regulation (over and under correction)

3.The ability to maintain the system for brief power interruptions (eg.up to 5mins)

4.Will shut down the computer before the battery is depleted but not restart it as most of my power interruptions seem to be just before I leave for work and I don't want the system restarting when I'm not here.

5. Availability in Australia.

6. Here's the tricky one, a sensible price tag. ($200 AUD. or less would be great.)

Thanks for any suggestions "?" (Yahoo called me "?" they seem to have misplaced my name!)