From South America to Oz by sea

Hey all, my wife and I are starting our RTW in June 2011. We will leave Canada for Central and South America, and then want to likely (it can all change so fast, can't it) head west towards a few south pacific islands and then Austrailia. Does any one know of any where to find sailboats or any sort of seacraft that might be taking a route similar to that, which might also take a couple of Canadians on board?

Also, anyone know how long a trek like that may take, in terms of total travel time, island hopping aside?

Thanks!