Home Winemaking Step by Step
This is a great book to sit down and read through before you begin making wine from grapes. It goes through each step a winemaker follows, from the equipment to the yeast, from fining to fermenting.

This might not be the best 'only one' book for an all-around winemaker - it concentrates on making wine from grapes, while most home winemakers foray extensively into fruit winemaking. Also, it doesn't have recipes in it, so you'll need a companion book to figure out what you're making. Still, this is a very valuable book and should be on the shelf of any home winemaker.
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