I love Vergelegen! My cousin (with whom we stayed) lived (and will move back soon) just a few blocks away from it!
Basically, you can just take your car and drive around, most farms have signs posted and you can just drive up and see if they do a tasting.
I am not big into wine, actually know nothing of it, I like some, dislike others. But the beautiful gardening on some of these wine estates, the gorgeous setting of the vineyards, the friendliness of the people, its just a nice place on earth!
According to my cousin, who loves wine, are the whites from down there very good, but he usually brings a few selected bottles from Europe back with him. Not that he goes by the red ones from down there for everyday use, lol.