Hermana Tonini has mentioned in both of her letters about services that deliver care packages to the Mexico City MTC. What is neat about these services is that they hand-deliver them to the MTC so you don't have to pay postage to Mexico or worry about the Mexican postal service (hopefully it is better than the Brazilian postal service - but I digress).
We used Missionary Package Mexico to send her a dozen Krispy Kreme doughnuts but they have a number of other options. Just Google "missionary package mexico" and you will find a number of sites that provide free delivery service to the MTC.
Don't forget - she is only there until February 27th! Let's show how much we love her!