Security doors

Just recently modified an existing aluminium security door(second hand) by reducing it's dimensions to suit another opening, after spraying the door with it's new color and fitting a new lock I was rewarded with oooh ahhh how nice is that! this has now inspired me to go further and form some window screens and doors from scratch, so I have a few questions?
Who are the suppliers of the extruded aluminium sections as well as the diamond grills that they use (Wholesale), there appears to be very little information about in this regard.
Thank's guys.

These guys do just about everything aluminium

Not sure where they are in Vic but here's there URL

http://www.alspec.com.au/

Try your yellow pages, there are about 10 in Newcastle
I generally use carpel and cut the grill section with a band saw with a suitable AL cutting blade about 16/18 tpi

Thank's for your reply guy's , I'll give em a ring when their back on the job, its all a matter of price versus quality I suppose, which is something I'll have to suss out.