There are a number of studies covering the North African theatre of war from beginning in June 1940, to end in May 1943. I would personally recommend getting hold of Colin Baxter's slightly-dated bibliography of the War in North Africa for further delving into the topic, since it is multi-faceted and some studies fail to do the entire period justice in one volume - Tunisia particularly, which I am writing my thesis on, is not that well-covered by any study really. However, I have listed some books which you may find interesting for a general overview of the theatre.

Robin Neillands, Eighth Army: The Triumphant Desert Army That Held the Axis at Bay from North Africa to the Alps, 1939-1945, 2004

John Bierman and Colin Smith, War Without Hate: The Desert Campaign of 1940-1943, Penguin: 2004

David Jablonski, Desert Warriors, New York: 1972

Bingham and Kaupt, The North African Campaign, 1940-1943, London: MacDonald, 1969

Anthony Farrar-Hockley, The War in the Desert, London: Faber and Faber, 1969

W.G.F. Jackson, The Battle for North Africa, 1940-43, New York: Mason/Charter, 1975

However, whilst these are all rather general, albeit most scholarly, texts, if you are not afraid of density I would simply suggest retrieving I.S.O. Playfair's Official History volumes from the library and delving into them, as they remain, in my opinion, the most detailed accounts of the North Africa Campaign available.