That brings back a few memories. I grew up on the water on the Sunshine Coast (Egmont) and spent many a summer day fishing perch.
There may be better methods nowadays, but this is how we used to do it. As their name (pile perch) implies, they like to hang around underwater structures that have lots of feed and shelter such as pilings and docks. They are cagey and have small mouths, so we'd use a small single hook (#12 or so IIRC) and small leader, with little or no weight (maybe a split shot). We'd grab a handful of mussels off the piling or dock. If there was a seaworm in there, then great, cut that up & use it. If not, just use mussel. The soft bits work great but don't last long; the heart & gills last longer. Or you can thread a whole small mussel on the hook then crush it. It's important to hide the shaft of the hook. Drop it down & watch. When they suck it in, set the hook.
That's what made it fun I think - you are watching the whole thing & it's a battle between you & the fish.
As for where to go, I would think you should be able to find them anywhere there are pilings at a government dock. If there are any public government docks in West Vancouver that would work. Or Snug Cove on Bowen Island, the government wharf in Gibsons, Porpoise Bay, Halfmoon Bay, Madeira Park, Garden Bay, Egmont etc. etc.
Good luck & have fun. As you mentioned, the hardest part is keeping shiners off the hook.