Dirk Vandewalle has done some impressive work on the Gaddafi regime itself, particularly in the importance of oil in its political economy.

Lisa Anderson is essential reading on Libya. Her writing on the regime itself is more limited (available mostly in articles rather than books) but her work on the lead up to the regime during the colonial period remains among the most comprehensive and important.

Jonathan Bearman has a book on Gaddafi that is better than many others, being both informative and amusing.

Mostly try to stick to academics when studying Libya, there are plenty of books on Gaddafi written by journalists that don't have the same critical eye or familiarity with the country that the scholars do and thus tend to do their best to talk up how interesting Gaddafi's personality was.

The Green Book is essential reading. You should be able to find a translation of it in your language of choice (produced by the regime itself, which is in itself telling and informative)

Ronald Bruce St John is more accessible and better than most non traditional academics as his work is submitted for peer review.

"Qaddafi's Libya in World Politics" is a great book on Libya's relationship with other countries.

While not about Libya or Iraq I would also suggest reading Lisa Anderson. William Cleveland has a good primer on Middleeastern history in general although, like much of its contemporary literature, it leaves out North Africa including Libya, but it should suit your purposes for modern history and context. Abun-Nasr's "A history of the Maghrib in the Islamic Period" does the same but exclusively for North Africa, leaving out Egypt.

When I get a chance I will revisit this and try to give you more specifics.

I would also caution you to be wary of sources you find online, particularly on certain blogs.