You can learn to use Tunisian Crochet symbols with the purchase of my Symbol Directory. Also included is a pattern for the Lucia Fingerless Mitts to help you practice reading the symbols. More information.
Or, if you are looking for more information on Tunisian crochet symbols and charts, my Tunisian Crochet Stitch Guide contains 61 stitch patterns, all written in charts with symbols. The first chapter teaches how to use the symbols and the remainder is all lovely stitch patterns.