Per "The Stationers' Company and the Printers of London", by Blayney, 2013, considered scholarly and definitive, Joan married Richard Pynson Jr, (1494/7-1520), son of Richard Pynson, one of the three most important of the earliest English printers. Blayney finds Richard Sr. to have been born in Normandy, Richard Jr. born in England. Joan was the mother of his children John(circa 1519-1540) and Joan (circa 1519-1537).
According to Blaney, Joan Rastell also married John Revell, of another printing/publishing family, and the dramatist John Heywood (although this geni.com record indicates Joan had a sister Elizabeth who married Heywood).