chipmonkey - depending on where in Ireland you are I am pretty sure you can get Dylon dye in Roches Stores in Cork for eg. Any department store with a decent haberdashery dept should do it - Arnotts in Dublin maybe?
the machine dye really is easy to use, and no problems with splodgeyness (technical term there ) which you can get with the hand dye if you don't stir enough or put too much stuff in to be dyed
haven't dyed nappies myself mind, but pretty much everything else under the sun has changed colour in my house, courtesy of Dylon