This is "old news" in the HP fandom I suppose, but Devon Murray (Seamus Finnigan in the films) is supposed to be appearing at Supanova this year, in Brisbane at least. More details can be found at the website here.
It's April for Brisbane and October for Sydney... I live in Sydney so hopefully he will come back in October! (I couldn't have afforded to go in April, anyway). If I can go, I plan on going in costume. Maybe I'll cosplay Tom Riddle. Sure, I'm female, but it's Tom! ;)