Know Walthamstow well used to hit the market there as a kid and a few nights at the dog track before it closed.
Lots of places in Margaret River mate a lot of it close to Dunsborough - a few ideas that may help:
Busselton - long jetty that's worth a walk on a nice day
Beaches: Meelup (nice small cove so easy currents & lovely beach), Yallingup (great place to go in late arvo/around sunset - take a few cold ones & park up on the hill watching the sunset & local surfers), Smiths beach (closer to Dunsborough are more smaller, relaxing, further down the coast are the larger wave surf beaches (e.g. Prevelly in Margaret River town, Grace Town, etc..)
Breweries: (nice for lunch & a beer): Duckstein (german themed - prob most fancy but nice setting - you may go there on your tour), Bootleg is cool (sometimes a band playing some chilled out tunes), Cheeky Monkey
Restaurants/Pubs: Caves House (Yallingup) - nice beer garden & pub grub food / Clancys Fish Pub is nice (beers & fish/chips/seafood)
Wineries: Too many & down to personal choice - just drive around & pop in for tastings
Other: Simmo's Ice Creamery (delicious!!), Gabriels/Marg River Chocolate factories, Cheese Factory, Providores (if you like chutneys/jams/sauces), Natural Olive Soap Factory (one for the girls - when my family came over a lot of them bought gifts from here), Caves you can go down, etc...
Hope this helps - could go on for a while as have been down 7 or 8 times now!
Cheers
Adam