Hey Matt!
First of all, this is the most important link you will need on the start of your journey:
http://www.talkbass.com/forum/showthread.php?t=43093
It's at the top of this forum, as a sticky. Take the time to search through it. We don't have the same luxury as our BG brethren to just walk into a music store, sit down and try a bass. We end up having to do a lot of research and travel to find the instrument we need, especially once you step past the beginner stages. Since you're going to have to take the time to get to places to try out basses, then you might as well put in the research time in terms of going to the
right places.
In regards to your location. I haven't heard of any prominent shops over in Ireland, but that doesn't mean they don't exist. Got any buddies who play violin, either in folk or classical? they might be able to give you a heads up on a reputable shop in your area. aside form that, there's the Contrabass Shoppe at
http://www.contrabass.co.uk/ (I find that website to be very finicky. i don't know why. they have a fine selection though). They're in England, somewhere in the London area I believe. That'd be a bit of a jaunt, but it might be worth it if you don't find anything promising in your area.
As you'll find in the links, You're gonna have to save up some bread to get an upright. even a plywood bass (most beginner basses are plywood, though not all plywood basses are "beginners") costs somewhere above $1500 USD, often more, for something thats worth even looking at. Brands? Well, everyone here has preferences, but it's less about brand and more about what instrument you see a potential in.
One final bit of advice: get into contact with someone who teaches upright in your area. Most people around here recommend a teacher so you don't hurt yourself from poor technique, but it also has the added advantage that when you're shopping, you've got someone unbiased whose brain you can pick for information.
Read the links on the "newbie" page, do your homework, and i'm sure you'll find something you like.
Sorry I talk so much.
eerbrev