The Western Australian Visitor Centre can provide more information.

http://www.westernaustralia.com/au/Pa...

 

Ferry: (half day/day)

Perth Zoo 

Swan River Cruises

Swan Valley

Rottnest Island (from Perth and Fremantle - often cheaper on Tuesdays)

Rottnest Fast Ferries

Charter Boat:

Whale Watching (from Hillarys Boat Harbour)

These are a few of the day tours available from Perth & Fremantle:

Mills Charters

Whale Watching Perth

Australian Whale Watching

Coach Tours: (1 day) 

Pinnacles Desert http://www.twatours.com.au/

Margaret River Region

Wave Rock/Hyden

Native Wildflowers - seasonal - August /October