Hi Snozberry, welcome back.
First of all, if you're just wanting to get a few dives in here or there, a dry suit isn't mandatory, it's obviously a great option for the cold waters of BC, but a 2 piece (14mm total, 7mm a piece) wetsuit will work just fine too, you'd save a bit of money that way as well. But, if you're set on taking the course, there are definitely some good shops in and around Vancouver that are worth visiting. Like others have said; Ocean Quest / IDC / The Edge, are great. At Langley Diving, we offer the dry suit course for $229 + tax, which includes your rental suit, all the dives, all gear except mask/fins/boots/snorkel, AND your cert card, which I don't believe the other shops include. I've got a lot of respect for all the others, and know you're in good hands wherever you may choose to go
Regarding dive sites; there's tons. If you haven't been to Porteau Cove, it's worth checking out. After a few dozen times it starts to get kind of boring, all the dive-shops tend to do training there, along with Whyte Cliff Park which is another great site (especially The Cut

). Other places close to Horse Shoe bay like Kelvin Grove offer a lot of things to see. The town of Sechelt has Tuwanek (favorite), and like others have said, the wrecks over in Nanaimo are good too.
You've got a lot of options! I'd try them all if you can. People on here are always looking to go out, even just pop into a shop, and you're bound to find a buddy.
Take care,
Tersch