Depends on the style you like but saw a lovely glass and chrome one in Woodies, Sandyford, yesterday, greatly reduced. They also have pretty funky looking computer chairs.
My mother got one of those a few years back and it's pretty good for her needs. Very sturdy and easy to assemble. There is not much desk space for working on though if you need that. The monitor takes up most of the top space.
I have a small desk we got from Atlantic last year which is OK but a bit flimsy and cheap looking. I have a desk from IKEA I've used for work for nearly 20 years and it still looks fantastic and will last another 20 - cost about £50 I think. Saw a really nice glass and metal computer desk in Cedarwood Kitchens in Enniscorthy a fortnight ago which was reduced to €90 including chair. But in the end I got a good size one for nothing from Wexford Freecycle last week and repainted it to match the room decor.