From vendors in/around the town using the vouchers.

What you actually get are vouchers. When you want to make good on any voucher, find a vendor for the item and redeem the voucher.

The vouchers can be redeemed either instantly if you're in Exposition (Bloodline+), or through the in-game vendors post-launch.

Some important details you might like to know, if you don't already:

1. Vendors do not have unlimited stock. What you see is what you get. They may only have multiples of 1 or the other gender, the animals may not be the desired age, or color, etc.

2. The animals generally vary by biome. Flowercup porcupines are likely to have different flower disguises based on biome, animals bred in the mountains are likely to have more endurance while their plains counterparts are likely to be faster. If you want a specific variance that isn't native to your home biome, you'll either have to pay to get it to you (which may go wrong, if the messenger is lost, waylaid, or killed, etc), or you'll have to go to the biome that the variance is in and get it yourself. Keep in mind that some variances may not do well in your biome - for example, a snow leopard is unlikely to enjoy the desert, and a shrubland wildcat might dislike the alpine forest.

3. Animals aren't immortal. They can die from battle wounds, they can die from old age, from starvation, from exposure, from being eaten by another animal, etc. They'll need to be taken care of properly if you want them to last.

4. Animals aren't automatically tame. They won't automatically follow you, so if you don't keep track of them, you'll lose them. If you don't house them properly, they might run away. If you don't train them well enough, they might eat you (predator pets). If you have no hand in their training, they have no reason to be loyal to you. They can also be stolen from you.

5. Animals can be bred by players for desired traits.