You can breed your starting male and female wolves. Also, in the campaign you can very rarely stumble across a wild wolf and you'll be given the option to bark or wag your tail. Pick one randomly (doesn't matter which) and if by chance the wolf likes you, it'll be added to your den with random colours/breed etc.
The easiest way to get wolves if you have currency is from the flea market. (Shop > Flea market > sort the category to lorwolves for sale.)
