Standard city view would be from King's Park, and now spring, there should be flowers at Kings Park too. Beaches can be Cottesloe and Hillaries (Near underwater world). Frementle would be good too. If you like swans, can go to Lake Monga. If you are more adventurous, you can go to Rottnest Island.
It's a bit early for wildflowers, the best time for them is around October.
Good places for photography in Perth include the already mentioned Kings park, as well as Hillaries, the foreshore opposite Perth (south river bank) around dusk, up near UWA on the beach. Also for Koalas and kangaroos try Yanchep National Park and if you want to spend 75 bucks take a whale watching tour out of Hillaries.
Other highly recommended locations. Rottnest Island (9km off Perth), Fremantle (street scenes, old buildings, gaol etc).
The swan valley (northern Perth outskirts) has some nice wineries and if you ask nicely they may give you permission to shoot inside the winery proper.
South: Meelup beach (stunning), Margaret River, Cape Naturaliste lighthouse, Sugarloaf Rock and Augusta all have good photographic potential.
North and North East of Perth (under 300km)
Cervantes/Pinnacles - stunning around sunset or just after dawn, but it's a 3.5 hr drive from Perth.
New Norcia - nice old buildings and a monestary (in use so you can't enter it to take photos).
Toodyay - Some nice buildings and landscapes on the way there.
Albany (lots to photograph there)
Albany to Margaret River - the major toursit destination in WA, lots to do and photograph.
Wave Rock - It's a big day trip (760km or so) and is stunning near sunset. Also good for the 'big flat' wide open no houses in sight shots.
Mulka's Cave (near Wave rock) .. Aboriginal hand painting that's about 400 years old.
I'm studying in the University of WA, which is in Perth. I hope I can help in this respect. Perth is a gorgeous place for photography. Here are some suggestions.......
1) Perth City Itself
Venture into the back alleys, the railway station, just walk ... and opportunities abound. Lots of baskers ard, as well as people performing.
Gorgeous. Check out the markets, check out the port, check out the prison.
3) Araluen National Park
Tulips abound, lots and lots of them. A bit botanical garden like, but lovely. These tulips are not wild though, but worth a visit. 50km from perth.
4) Kings Park
hmm..... now they have the wildflower festival. Nothing spectacular honestly, but do check out the city views. But, honestly, boring.
5) Uni of Western Australia
Worth a look for architectural shots. Lots of weddings taken here.
6) Down South
Take a drive down south, up to Albany. Now is THE time. Spring is here, flowers are everywhere. Lovely weather. See margaret river, etc. Wild fields of lilies. You will have to stop every 5 km to take pictures, cannot take finish man. Hope its digital. The landscape is breathtaking along the coast line where massive swells pound the coast. Esperance is unbelievably beautiful.
7) Up North
Another gorgeous trip. The landscape is different, more harsh, but more dramatic. The coastline is rugged, very rugged. Drive up to Kalbarri to see gorges, rivers, orange soil, canoeing. Monkey Mia has beautiful beaches where dolphins swim rite up to u.
Honestly, now is the best time to visit perth. Bring tons of film. You're gonna love it. I can help you if you want. Just drop me a message. Near Perth also got nice stuff, like Serpentine falls. Do a search in the landscape forum, I have a post there. You're in luck dude, the flowers are out !