Next door to Zlý Časy, Prague’s most famous multi-tap pub, is Pivkupectví. Also operated in conjunction with Zlý Časy, this little shop has one wall lined with fridges, another with shelves, a back room specializing in Czech beer, and glasses and tee-shirts. All of the big name Czech breweries can bought freshly here; Matuška and Kocour for example, are well stocked.
For hard to find breweries from abroad, this is a great place to shop- they always have a few bottles of Mikkeller, BrewDog, and Mooi & Meedogenloos from De Molen. Service is friendly and helpful. This is just a beer shop (and one of Prague’s best at that!) but if you’re thirsty, just walk next door and see what’s on tap.