All of those sites are good sites but there are about 6-8 different types of calls for turkey what i did when i was first learning to call was made up index cards that said like Yelp - How to do it on each call and how i am expecting the turkey to respond. That way you can know what each call is and learn them little quicker and you can just take it in the field with you if your using a blind read up on them. Just a suggestion