Token are widely used in the Yu-Gi-Oh TCG and always represent face-up Monster Cards. They are always Special Summoned by a card effect, cannot be included in the Deck, Extra Deck or Side Deck and the original ATK, DEF, Level, Name, Type and Attribute is stated on the card that Summons them.
Some also have effects applied to them by the card that summons them, but they are not the effects of the Token itself.
You should be able to use any Token card (fan-made or not) in most tournaments.