The World Communion of Reformed Churches is the largest association of Reformed churches worldwide, representing more than 80 million Christians in 229 denominations throughout 108 countries.
The most well known include the Presbyterian Church (USA), the Church of Scotland, and the Dutch Reformed Church.
Yes, Calvinism is still believed in a number of different churches. The "Reformed Theology" follows all the teachings of Calvin as outlined in their statements of faith, and Heidelberg Catechism. A couple of denominations that follow Calvin's teachings include: The Reformed Church and The Christian Reformed Church.
The Reformed Church was founded by Ulrich Zwingli in Zurich in the period 1516-1519. The Reformed Church in the United States (German Reformed) was founded in 1725. The Dutch Reformed Church was founded in the U.S. in 1628.
Lutherans began as a movement to follow the teachings of Martin Luther, a German Catholic Priest trying to solve systemic problems in the Catholic Church. The Reformed Church is theologically very similar, but was started by the Dutch. They are both major Protestant Denominations. Neither one is considered a part of the other.
Third Reformed Church was created in 1875.
Reformed Church of Shawangunk was created in 1755.
Reformed Church of Beacon was created in 1859.
Dutch Reformed Church was created in 1571.
Winfield Reformed Church was created in 1880.
The Reformed Church of Newtown was created in 1731.
Reformed Episcopal Church was created in 1873.
Niskayuna Reformed Church was created in 1852.
Middlebush Reformed Church was created in 1834.