The events used to book end of June/first part of July. They have booked later every year since. Last year, reservations opened around August 9th or so (I don't recall the exact date).
You can enjoy food, wine and beer at the 20 or so booths set up around World Showcase in Epcot, representing various countries (or, I suppose this year various "foodie" cities around the world). The theme is "Cities in Wonderland", which I have to admit I don't begin to understand. You can enjoy the booths, as well as wine seminars and cooking demonstrations by paying your admission to Epcot and then paying for the foods and wines you sample from the booths. The wine seminars and cooking demonstrations are generally free, except of course for your initial Epcot ticket admission.
As for the other wine and dining events, they are separate ticket events. You have to book them when WDW makes reservations available. They are non-refundable and can get pricey. If prices are about the same as last year, wine dinners will range from $150 to $185 or so per person, with a much higher tariff -- $350 or so per person -- for the V&A dinner if one is held. Party for the Senses was about $130 per person last year. Vertical wine tastings were around $100 per person as I recall. Food and wine pairings at Epcot restaurants are one of the better values at about $45 per person. We haven't done some of the other events, so I don't recall those prices.