The main normal driving head light failed, I thought no probs, I will get the dead bulb and go find one the same and replace it.

I am talking about the little round ones in the light unit, (not the lower fog lights).

It seems to be a self contained spot light kind of thing that I can't get out without a short little Phillips head screw driver, is this a normal buld replacement or a special light that you have to buy the whole thing from Isuzu after the holidays.

It is about a 5 year old model.

You will only need a globe. Wait till you can find any spare part or motor shop that is open after the holidays. They will normally pull out and fit for free a 1 minute job. Don't need to go to Isuzu.

Um......have you tried opening the hood/bonnet and removing the rubber bulb/globe receptacle from the light unit?

Do this, remove the bulb, get a replacement, reverse the procedure.