Dublin's not that bad for street skating. Now granted, it's not like Paris for simply cruising or Barcelona for the abundance of spots, but still, it's good laugh to skate around the inner city - forget about the immediate city centre itself, but there's been a fuckton of recent construction along both sides of the river Liffey going out to sea. You might have some luck with finding a few random spots, meet up with some locals who'll show you around as the majority of stuff isn't necessarily the easiest to find. Saying that, check out
http://www.skateeire.ie for more info - hopefully you'll get skating at the recently reclaimed Bank of Ireland on Baggot St. Think of MACBA with skatestoppers, cold & rain and you're there. Wicked spot though, ha.
Peter's Pub & Grogan's, both on Sth William St and the Long Hall just around the corner on George's St are non-touristy & worth checking for the more trad vibes.
One thing though is that Ireland is eye-wateringly expensive, with similar costs to Helsinki or Copenhagen, but without the fantastic Nordic chicks - ?6 for yer average beer in a pub and everything else is commensurate with that.
As Pregnant Head said, avoid Temple Bar. It's just shit. It's a tourist trap full of tourists (who'd have thought...) and far too many fuckwits who may not necessarily be tourists.
You might want to look into spending a weekend in Dublin and a week in London. LDN is enormous with so much going on that you need a few more days to take stock of what you want to get up to and getting to know the lie of the land - you'll often be quicker walking 1-2 Tube stops than going on the underground itself, that sort of thing.
Mile End skatepark (E. London) has a shop on site -
Parlour - or if you don't make it out that far, try calling into Slam City in Neal's Yard in Covent Garden and grill them for info.