What are you using to measure your resistances and where are you checking? A good glow plug is typically .7-.9Ω. 0Ω usually indicates a short circuit.

If you have no glow light, check to see if the strip fuse in the glow plug is broken or cracked. Check the bulb in the dash to see if it is any good. It's also not uncommon for the glow plug relay to have issues.