I've bought beer online from mostly Drinkstore and O'Briens, and Deveneys and some Belgian site years back. Don't do it much, I certainly do it at Christmas though. The local O'Briens is very well stocked with craft beers, maybe as good as Drinkstore or Devennys, bar the odd hard to find ones. Also ordered online because the Americans used to be hard to get, but as someone else said 8 Degrees are now doing IPA's to beat the band, so buying Irish much more often now. Haven't bought anything from beers of europe or beernavigator, as the shipping knocks the price of a bottle up 50c or a euro. Drinkstore give us a discount, and O'Briens have 6 for 5 deals, and free shipping over a certain amount too. But I'll always pop into an off licence to see if they've anything new.
Aaron