Go to the Burrow and Diagon Alley. Look for chests there for Wizard Cards.
Go Neville's games, especially Broom Racing, to get Wizard Cards. Note: You will have to pay Beans to participate in Broom Racing and Gnome Tossing, Gnome Dunking is free.
In Ron's barn at the very beginning is a card on top of the rafters. To get it, you need to climb the chicken coop outside.
Go to the fourth floor. Look under every bookshelf. You should notice there is no wall under one of them. The path leads to three treasure chests, revealing Wizard And Witches Cards.
When in Fred and George's Shop, go to the card nearest to the bathroom stalls. When you press X to hear information on the card, Harry will say instead of naming the card "How much is this Famous Witches and Wizrds Card?". It will still cost thirty Beans, but you will get one of the cards you missed. It will reappear after you purchase it. The order you receive them is from the first one you missed to the most recent one you missed.
Go to the fourth floor and look for a staircase that has no wall under it. It will say "Crawling" in the top corner. Go in it and explore to find two Wizard Cards and a cauldron for refilling your potion vial.
Go outside and look for flame torches. Light all of them with Incendio to find a chest. A Wizard Card will be inside. The torches will be on top of towers.
Look for groups of torches while you are flying above Hogwarts. Land and light the entire group of torches. When you have done this, a chest will appear with a Wizard Card inside. You can find the torches near where you located the Dragon Hide Gloves, on a rooftop, and in a courtyard.
When you get your Nimbus 2000 from Oliver Wood, get on your broom and fly over the flying lessons area, and directly over the confiscated items storeroom. There will be a window that is half open. Run into it on your broom and you will get a free Wizard Card.
When you read one of the books in the Library, it tells of a boy who kept a Wizard Card in a broken window. Fly on your broomstick to one of the tower ledges. You should find a window that is broken and has two boards covering the top and bottom of it. Get on your broomstick and ram the window. A Wizard Card will appear.
Once you have the key to the Confiscated Items Storage room, there is a chest with a bag of beans. To get more Wizard Cards, you can go to Fred and George's little shop and buy them. Then, in a corner there is a Wizard Card that keeps reappearing. You can buy it repeatedly, but it will be a different wizard each time. Eventually you will run out of beans. Just fly back to the storage room and get the bag of beans again. This bean bag will keep reappearing every time you go back.
