Modifying your diet will help your general, overall health, which shows in your skin. Drink lots of water, steer clear of junk (despite how cheap it is), and take a multivitamin. You don't need to take anything fancy or expensive. Oh, and sleep is a must! A good night's sleep is essential to good skin.
But to help you negotiate the massive amounts of products available at your local supermarket:
As far as topical cleansers go, you want to find one that's gentle, will remove oil, but also won't leave your skin dry. Neutrogena makes a basic foaming cleanser that is perfect for this (they have two that are good, their Fresh Foaming Cleanser and their Extra-Gentle Cleanser). Cetaphil is also a good one (though I'm not sure if it's available in NZ). As for getting your skin to "perk" up, any moisturizer (and yes, you should use moisturizer, male or not) with soy compounds is good. The soy isoflavones promote a more even, brighter complexion. Look for anything that says "skin brightening" on the label and then check for the soy isoflavones. Using a moisturizer with alpha hydroxy acids (lactic acid, glycolic acid) can also promote a brighter, more even complexion. The alpha hydroxy is also good for clearing up acne
