A few of my suggestions - and will add more as I think about them.
Whiteman Park - Motor museum, and much more.
http://www.whitemanpark.com.au/A beaches drive - there's plenty of them, and some nice drives fairly close to the water. Some pubs and eateries along the way. Also a chance to see a sunset over the ocean - you won't find that on the East Coast!
Kings Park - Close to the CBD and some nice drives through the bush. Great views of the city, tree top walk and places to eat.
Fremantle - As has been mentioned, lots of micro brewery's and restaurants and beautiful buildings. The Fremantle Prison is definitely worth a look, and does tours of the tunnels underneath. Also the Maritime Museum, Fisherman's Harbour and the markets. And a great place to cruise up and down the strip in a Moke.
Rottnest Island - Good for a day trip by ferry. If you want to stay overnight I'd start booking now...
Swan Valley - Very close to Perth with Wineries, Breweries, Chocolate factory, art galleries etc. Easy day trip.
Mundaring Weir - Nice drive through the hills east of Perth, and the weir that supplies all the water to the Goldfields. No 1 Pump Station is open on weekends.
South West - Bunbury, Busselton, Dunsborough, Yallingup, Margaret River etc. Again, lots of wineries, breweries, forests, caves etc all separated by some fantastic scenery and Moke roads. Not really do-able in a day, but there's plenty of places to stay - and highly recommended!
Bonn Scott, Rock & Roll dude!
Thats better I am just going for a drive
Now youre talking!
There's a statue at Freo Fisherman's Harbour, or better is a trip to Freo Cemetery. Happy to take you there - but BYO joint and stubby to leave for Bon.
Railway museum Guildford (?)
Do you mean the Midland Workshops?
http://www.midlandatelier.com/about/history-of-the-siteCheers, MD.