Not a silly question at all.... I see from your profile that you are from the United States so I will answer the question accordingly. My answer for other countries would vary widely... The general answer to your question is so long as they are a licensed acupuncturist they are going to be just fine for you. The only real stipulation from my perspective is when you have something fairly serious going on (cancer, complex neurological conditions, very complex psychiatric conditions, etc.) you may need someone with specific experience in those areas or simply just more experience.
On a general note there are (3) types of people that can practice in the US (some state laws vary) and they are licensed acupuncturists, doctors, and chiropractors. Not to judge doctors or chiropractors in any way but they are best treating relatively simple pain cases in conjunction with what they already do. The reason for this is they are not required (and very, very rarely pursue - although some do) the strong theoretical training and practical expertise required for the proper application of Chinese Medicine. In short, western doctors study western medicine and may do a few hundred hours of acupuncture theory and acupuncturists spend all of their time with Chinese Medicine.
Technically speaking there is no such thing as "board certification" for acupuncturists. We have a national certification agency which controls testing and is often required to receive state licensure. You can, however, (again in some states) drop your national certification and retain your state license. So the abscence of national certification means little in many cases. Generally, however, I would see someone who is both nationally certified and they will be, of course, licensed in their state.
Really for fully trained acupuncturists there isn't a bad acupuncturist per se. There are, however, different styles (japanese, five element, tcm, etc.) and within different techniques (strong needling, light needling) and various adjunctives (massage, etc.) It is these that you might find you have a preference for. But, while possible, I wouldn't worry about anything bad happening from a fully trained and licensed acupuncturist.
As a side note, you can read more about the styles of acupuncturists within our introduction to acupuncture article.