i found that metal ducking tape(the shit you use for air conditioning vents and so) works pretty good. draw a pic and use a stencil blade or scissors to cut it out. there whether proof and a bitch to remove.
i have the same problem i heard you can order a pack of 500 hundred of them for free but I'm just not sure where
^^ probaly thinking of us postal service stickers, if i remember right they may have discontinued them, as far as "hello" stickers, walmart or k mart, any mart store around.. otherwise ironlak has them at their store, black or pink and they say "G'DAY MY NAME IS" pretty neato.
ive been there in the united states a while back, they have good prices, nice store layout i dont think its appropriate to say they suck, they are an all around good store!