Is it possible to try Guild Wars like in WoW¨with a 10 days free trial????

Answer 1

No, since Guild Wars is a one time payment.

Answer 2

Yes there are trial keys available that give you 10 hours play or 14 days (whichever comes first.) They are called Buddy keys and come bundled with the game. If you have a friend that plays ask him if you can use his buddy key.

If you can't find a buddy key, Gamestop stores sell trial packs at the register for $1.99.