Sorry for the thread drift, but the question of why we spell Gaddafi's name in a variety of ways is very simple. As Arabic uses a different script from ours and has, for many of its letters, an inexact correspondence to our phonetic system, we transliterate Arabic names into what we think is the nearest equivalent. This explains why there are, for example, so many different spellings of the name "Mohammed". Even by reading Gaddafi's name with a "d", we are actually pronouncing the letter with a North African accent. In Standard Arabic it would be a soft "th" (as in "with").

It also works the other way round. Westerners may find their names spelt differently in Arabic by different Arabic speakers.