You can get free prayers to St. Joseph on the websites of the Eternal Word Television Network, Catholic Online and the Contemplatives of Saint Joseph. Some of the prayers are for specific intentions or activities, such as for success in work, whereas others are composed by a particular saint.
The Eternal Word Television Network offers a free Thirty Days' Prayer to St. Joseph, which includes both set lines and a space for the one praying to make a personal request. The prayer also invokes several moments from the life of St. Joseph that are either implicitly or explicitly contained in the Bible.
St. Joseph prayers that are available for free on Catholic Online include the Consecration to Saint Joseph (Of Children By Their Parents), A Devotion in Honour of the Seven Sorrows and Joys of Saint Joseph, Prayer to Saint Joseph for Sanctification of Labour, Prayer to Saint Joseph for Success in Work, and Prayer to St. Joseph by Pope St. Pius X.
The Contemplatives of Saint Joseph offers the St. Joseph Novena, Prayer to St. Joseph for Assistance, Prayer to St. Joseph in time of Distress, Prayer to St. Joseph for the Unemployed and The Seven Sorrows and Seven Joys of St. Joseph.