Our dog had a lot of fear issues when she was a pup, too. She was beat up in the shelter by the mother of another littler a few days before we got her, so she was scared of all dogs bigger than she. We made friends with the local pet supply store owner, who had her dogs at the store with her all the time, and who allowed people to bring their dogs into the store on leash. We'd bring our pup to the store and just hang out for a few hours a few days a week. She met lots of new, friendly dogs in a controlled environment, and eventually got over her issues.