Methods of manufacturing rotor blade components for a wind turbine and rotor blade components produced in accordance with such methods are disclosed. In one embodiment, the method generally includes heating first and second sheets of thermoplastic material to a forming temperature; placing the first sheet of thermoplastic material within a first half of a thermoforming mold and the second sheet of thermoplastic material in an opposite, second half of the thermoforming mold; forming the first sheet of thermoplastic material to the first half of the thermoforming mold; forming the second sheet of thermoplastic material to the second half of the thermoforming mold; compressing the first and second halves of the thermoforming mold so as to join at least a portion of the first and second sheets together; and, releasing the joined first and second sheets of thermoplastic material from the thermoforming mold so as to form the rotor blade component.