I think that the first report about Letizia's own tiara came from El Mundo in August 2010. They reported that Felipe had ordered it from Ansorena and that it had pearls in it. But they didn't know what it really looked like.
Some weeks later Ansorena came out with an interview to HOLA. They showed pictures of Letizia's tiara and similar pieces which were for sale at their company. They also contradicted the report from El Mundo, saying that the tiara was not ordered by the Prince of Asturias. It was the late owner of Ansorena who first had the idea of making a tiara for the new Princess, and after his death his sons proceeded with the idea. The article vaguely made it sound as if the tiara was a gift from the jeweller, but they carefully avoided any clear statement of who payed for it.
I have never read any clear proof about who gave it to her. If you ask me, that point was carefully kept in the dark.
Until now, these are the only info we have. Do you have any other? 
