I'm not LDS (Mormon), but my Brother and Sister in law are. Their oldest son just entered the Provo Missionary Training Center (MTC) three days after Easter. I felt like we ought to write him, support his endeavor, but am lazy about mail. Imagine my pleasure to find that I could mail him right from my computer!!
I was pointed towards DearElder.com. I sure like the ease of this! They deliver to the Provo MTC daily and with no charge for me. It is free for some missions and I think the letters will be sent to all missions, but you can donate if you want or feel so moved. You can also choose to purchase a care package to be sent to your missionary. I understand that missionaries LOVE cookies and brownies, so I may be taking care of his craving soon.
So Elder TJ, expect to hear from us more often! Good luck on your learning!