See that? Even the spiders are smiling in Wizard101! It's a good time!
So we have basically 4 major types of spiders we can own as pets:
1- The brown spider. The brown spider is your most common form of spider out of the bunch. You can buy yourself a brown spider for 5050 gold in the Mooshu pet shop. Sometimes people will buy and sell those at the bazaar, but it's not terribly common to see a brown spider at the bazaar I don't think.
2- The black spider. That's the bad boy pictured in the concept art there. You can pick your black spider up at the Knight's Court in Marleybone by defeating the Black Widow.
3- Lava Spider/Ash Spider. This is the crowns spider you can pick up in Wizard City. The Ash Spider has no stats, but it is the all black look. It runs 1490 crowns. The Lava Spider has +50 life and +50 mana, so it's a good choice for a newbie character for sure. That +50 mana goes a long way. It runs 2440 crowns.
4- Spider Golem. This is the rare one of the bunch, and is probably the most rare pet in the game currently. You can only get this in Kensington Park from Stoker OR from defeating the end boss in the master tower during the Halloween events. And to make matters worse, there is no second chance chest for Stoker (but you do get to fight him twice during the Kensington Instance).
I managed to get my friend Tipa to join my conga line this morning so we could get a picture of all the spiders together, YAY! Tipa is the only one I know with the Spider Golem pet. She rocks.
So get your little scurriers out of the backpack today and let 'em creep your friends out! Now if only we could ride on a spider!