OMGOMGOMG! I found Tim Tams HERE!! Not just in Australia, but here in Colorado!!!
For those unfamiliar with Tim Tams, they are about the yummiest cookie/biscuit in the whole world. I got the chocolate ones. It's two chocolate cookies with chocolate cookie cream - not quite as sweet as Oreo - then covered in milk chocolate.
I found them at Cost Plus World Market. I don't know if they have national locations, but there are 3 in the Denver-metro area (Southwest Plaza, Park Meadows, and Boulder). That place has SO much stuff! Just the food department - sparkling water from Norway, international ethnic chocolate, marinara sauce from Italy, REAL Cadburry chocolates from the UK (will try those on the next trip), Haribo gummi bears from Germany, and I seriously about jumped out of my skin when I asked the girl if they had Tim Tams and she said YES! They are under the name of Arnott's, but she assured me that they are Tim Tams, made in Australia.