Write down all dates of contact and notes on what is/was said. That in itself is often enough proof and shows you were promised specific things on specific dates etc. The average judge will not think you are going to go way out of your way to make up stuff just to take someone to small claims, if it goes to that.
It also might not hurt to remind the breeder "last time we spoke, you said this and this". If it ends up in small claims you want as much on your side as possible so send a registered letter clearly stateing their promises and what you expect in return, if nothing else you can be sure your side of the contract was clearly understood by you and them, and they can not later dispute "oh but I thought they ment this instead..". For a contract to be valid both parties must understand and agree on terms. Even if you only have a verbal contact over the phone, as long as there is understanding and something going on each side as in buyer/seller exchange, that is a contract.
If they leave any messages on your answering machine, those are also good to keep a hold of also. Of course, there is also the possiblity they are just lazy and not "on the ball" and not following up as quickly as they should but have every intention of doing so.. maybe they really are forgetful and such.. but still, if they sold you something they have a responsiblity to uphold, and dont be afraid to pursue getting what you deserve.
PS. I am not a lawyer.