You can find Linearts and bases for them on deviantart.com
However, make sure the linearts are *allowed to be used for digital currency* or something along those lines.
Usually adopts involve something like: capturing an adopt, and allows the customer to choose baits which will aid their capture of a "better" adopt.
After capturing, it usually also have a breeding option to breed two adopts for more adopts.
If you have any specific questions, please ask ^^ I'm not sure which part you're confused about.
Fall Month: 3 
Night 
Fog Moon: 
