There also seems to be a big misunderstanding about a traditional tatoo done by a Monk. You don't have a choice of the design, and very little choice on where it's placed. They are done for a number of different reasons, with health being the most prevelant, and spiritual safety coming in a close second.
There are less than a handful of Monks that have the powers to do traditional tatoos in all of Thailand. Only one that I know of in Bangkok, and not the one Angela Joliet used.