I saw someone post a thread on widescreen hack and googled a little, it seems work on netbook too.
Hack applied, screen looks much better then default 800x600, but upper part of the screen is missing!

Below is the shortcut I'm using, did I miss something?
"C:\GOG Games\SimCity 4 Deluxe Edition\Apps\SimCity 4.exe" -CPUCount:1 -CustomResolution:enabled -r1024x600x32

My netbook spec
Asus Eee PC 1001PX
Atom N450
1G Ram
Screen 1024 x 600

800x600 screenshot revised to reflect the actual picture saw on screen

My guess is that it's using the 1024x768 UI, which expects to have at least 750 pixels available. Try switching it to something else like 1023x600. That may force it to use the 800x600 one.

No luck with that but thinks for your suggestion