Coode st, good parking facillities just get there before the picnic crowd. There are a lot of dedicated bays for boat and trailers there. Reasonable ramp with beach either side which makes it very easy.

Try up river a bit. Maylands have a good ramp, Bayswater oposite Ascot race coarse, Kattaning street Bassendean just near the redcliffe bridge. Nice cruise up to the city and back. All of those ramps now have floating jetties to help with launch and retrieve.

 Cheers fellas thanks for the info

 maylands has a hose out by the toilets, best ramp Hose pressure I've ever used. 

 I'd avoid coode st if you've got a biggish boat. The ramp is usually sandy, and pretty shallow at times. 

I'd go with the other guys sugestions of launching upriver a bitt. Theres about threee or four decent ramps on the NOR side between maylands and guilford way. 

Have a little readof this for more info: http://www.hotbite.com.au/content/fishing_articles_wa/?thePage=5

It is a bit outdated, but many of the ramps havent changed.

 the ramp near uwa, matilda bay?, is great if you just want to potter around the city stretch

 the one down near the raffles hotel is good, is that called deep water point. did it on a busy sunday plenty of parking nice areas to picnic and couple pubs, launched a 5.5 ali

 also avoid mossies boat ramp if boats bigger than 4.5mtrs,royal perth public boat ramp is good