Clinics for Amish disorders:
General Information on the Amish
General Information on Genetics
The Genetics Home Reference is a comprehensive resource for human genetics information. It contains information on genes, chromosomes, mutations, inherited diseases, gene testing and much more. It contains a glossary of terms and extensive links to other resources. This is probably the best place to start learning about human genetic disease.
Websites for Medical & Molecular Geneticists
The following website hosts a database of Genetic disorders identified in plain people. It has a search facility allowing you to search by disorder, mutation or clinical phenotype.
Information on specific disorders can be found here.