the vendors you mean the sellers or the people who hatch eggs well for vendors there is 1 and for the sellers too much : )
The pet pavilion is connected to the Commons of Wizard City.
Wizard City, Pet Pavillion
you go to wizard city hatchery and ask someone to hatch it must be a lvl 48 pet or higher
Go to the pet pavillion in the commons,(wizard city), then play some of the mini games to get experience for your pet. If you are in wizard city and you can't find pet pavillion, click your compass on the left hand corner of your screen. It should lead you to the pet pavillion.
there is none
You have to level it up in the petpavillion
SUMMERDRADON gets you a dragon.
You have to have a pet
When you want to train a pet, you head on over to the Pet Pavilion in Wizard City. You can get to it from the Commons. Play one of the games available, do your best , have fun and at the end of the game, if you have any, give your pet a pet snack. Repeat this multiple times. Doing so will cause your pet to gain experience, therefore training them. Eventually they will level/rank up.
Nope.
You go to the Pet shops in the Wizard City and buy them for a little under 15000 crowns. :P
The pet store in wizard 101 is at Shopping District. Use your map at you journal. Or your compass.