I live in Port Coquitlam and my ready-to-go 75 gal aquarium will be delivered (thanks hidden reef

) sometime in the next week.
Where would you recommend getting live rock/sand?
I also wouldn't mind getting it used if anyone is selling or know who's selling.
Also, I'm thinking I'll get 60 lbs? I know the typical thing is to get 1-1.5 lbs per gallon, but I don't know if i want that much? Do I? haha.
Sorry if i sound horrible "noobish" but my only prior tank experience is at most a 10 gal with goldfish.
I'm not taking the plunge blind though,
I've been researching hardcore about marine aquariums, so i have a good base knowledge.