There's always one in Cork and Galway - The galway one was in MAy and the Cork one is in November.
I went to one in Galway last year - it is pretty good, plenty of stands and good ideas.
I went there last year and found it complete useless.
Just a a fistful of brochures. No real self build info , just products. Seemed more trade oriented than consumer. Also got stuck in traffic getting back, didnt help humour!
Went to Punchestown myself last year, came out with a truck load of brochures, but didn't get to speak to anyone that I wished too. Trade counters were to packed and busy. Have actually found this web site and another similar one much more useful.