Hans Von Luck's Panzer Commander is a good read. It's not a complete whitewash of his role in WWII, but it is biased (as are most memoirs). He served in nearly every corner of the war. In particular, I found his post D-Day accounts to be compelling.

I think von Manstein and Guderian are worth a read. They are NOT unbiased though, and seek to place all blame for the war's military failures and atrocities on Hitler and the SS, and avoid any blame for themselves or the German Army and General Staff as institutions.

Rudolf Höss (the commandant of Auschwitz-Birkenau) wrote a patently self-serving autobiography before his trial. Although Höss comes across as a particularly loathsome individual, it's an important window into how some of those involved in Nazi genocide conceived of and presented themselves. Höss takes great pride on being an able administrator and the memoir has the gall at times to be self-pitying (he talks of salving his conscience by going on long horse-back rides in the Polish countryside).

As for German generals' memoirs, to paraphrase Gerhard Weinberg: their consistent mantra is "if only the Führer had listened to me..." but they never finish it with "then the war would have lasted another three months and then the Americans would have dropped the atomic bomb on us."

Albert Speer's "Inside the Third Reich" is a very good look at the inner workings of Hitler's day-to-day, changing Nazi policy, and the German war machine/industry.

However, it was written when he was imprisoned at Spandau, and while the facts are straight, his opinions and recountings of interactions should be taken with a grain of salt. Lots or credible historians are pretty sure he messed with some facts to paint himself in a better light.

Look for a book called 'forgotten soldier' by Guy Sajer. It's an easy read, and not written from a general's perspective.