NANTUCKET, Mass. – More than 20 years ago, Peter R. Jarosewycz was looking for a way to contribute to the community of Ukrainians in the United States. At the time, Mr. Jarosewycz was a 52-year-old attorney living in Kansas City, Mo., far removed from the larger pockets of Ukrainian Americans in Chicago, New York, New Jersey or elsewhere. But he believed he could still contribute in some way.