My local Camperdown Cellars is amazing! I'm crazy about craft beer, and the selection here is off the charts. They've also got a 10% discount for 4 or more assorted imported beers, which means in my mixed six pack I usually get one free. ;)
The staff are also really enthusiastic about their products, and will occasionally hold up the line at the register to let you know how much they like your purchase, and what to get next time if you like it!
Bonus - the Ben and Jerry's icecream freezer right at the entrance. I can never help myself. :)
Jim's Cellars in Crows Nest is a good one. The shop has a nice fit out, and they have a good selection of imported stuff. Always have some specials going on in the front area of the store too. And as a bonus, if you're not in the area you can shop online from them.
Living way out in the west we tend lack quirky, interesting little bottle shops. But I have been to Paddington in recent times, walked into one of their cellars and found myself deeply envious of the ambience, service and the range of wines.