Hi, Christine!
I visited Vietnam in 1997, and, having heard about Mama Tina's orphanage, walked out there from the main tourist street... it's not very far. We just turned up at the door and asked could we have a look... not very thoughtful of us, in retrospect, and they could have just said "No, go away and phone for an appointment!" as they are VERY busy people. But, no.... the officer in charge, Christine Byrne (Mama Tina herself was abroad on a fund-raising campaign) personally showed us round for an hour or two, and we were terribly moved and impressed, more than I can tell you. By the end of the tour we were ready to forget our homes and just stay there for the rest of our lives. Eventually, commonsense (or maybe it was cowardice!) took over and we made our departure, but the idea of staying on never really left me, and to this minute I still carry Christine's card around in my wallet. I can, therefore, give you all the details of the street address, mailing address (so you can be more polite than we were, and write first) and telefax number. However, it may be abusing her privacy to post this on a public forum, so if you really want this information, could you please email me privately and I will send it to you?
I hope you do go ahead with your plan to visit, as this was one of our most memorable experiences in Vietnam.... and, believe me, it's a country full of memorable experiences!