You could try finding a naturopath. But as alternativista said, be sure that the test includes IgG (and maybe IgA).
Here's a little what various institutes around the world has to say about those IgG tests.
From the American Academy of Allergy, Asthma and Immunology & American College of Allergy, Asthma and Immunology:
IgG and IgG subclass antibody tests for food allergy do not have clinical relevance, are not validated, lack sufficient quality control, and should not be performed.
From Australasian Society of Clinical Immunology and Allergy (ASCIA):
There is no credible evidence that measuring IgG antibodies is useful for diagnosing food allergy or intolerance, nor that IgG antibodies cause symptoms.
From the Allergy Society of South Africa, Position Statement: ALCAT and IgG Allergy & Intolerance Tests:
the IgG food antibody test is being used to diagnose food intolerance in the absence of stringent scientific evidence. We urge general practitioners, pharmacists and charities not to endorse the use of these products until conclusive proof of their efficacy has been established.
From the Food Allergy Initiative:
IgG antibodies are found in both allergic and non-allergic people. Experts believe that the production of IgG antibodies is a normal response to eating food and that this test is not helpful in diagnosing a food allergy.
So as you can see, if you take those tests you are going to become a really paranoid person, just like 95% of the people in the diet and holistic health section of the forum. It's the same thing with religion, when someone is really desperate like gets sentenced life to prison or in death row, they usually starts to believe in god. But we all have to make that choice in our own little heads.
Yeah I've seen most of those dissents. Lacking controls and evidence does not mean that there is in fact no benefit to taking the tests. As the Allergy Society of South Africa states, more research is required before we can know for certain whether or not these tests are useful. Until then, it could go either way.
I'm more concerned, though, with the fact that these dissents address allergy and food intolerances. Allergy involves IgE, which isn't being disputed here, and food intolerances are usually considered by the conventional medical community to be limited to gluten and lactose. When they aren't, they are hard to identify and diagnose because they are often less severe, chronic, and delayed from time of ingestion of the food in question. This makes me question the wisdom of these critiques in assuming the "healthy subjects with raised IgG for several foods" were actually healthy. Not all inflammation is readily visible, or can even be felt by the subject.
The fact that IgG antibodies are found in allergic and non-allergic people has little relevance when it comes to intolerance, which is distinct from allergy. Again I'm concerned with how often allergy and intolerance are conflated.
Suggesting that raised IgG is a normal response to eating food seems a bit strange. Why don't we all have raised IgG to all the foods we eat? Why is it instead just a few? There is a distinction here that is not being made, and should be made, because clearly our bodies react differently to some foods, and raised IgG to some foods by definition is an example of that differential in reaction. Whether or not it is causing damage due to this IgG interaction can be questioned, but it isn't valid to assume that there is no damage being done just because there is not yet any evidence of damage being done, especially considering the low-grade chronic nature of food intolerances (as well as a wide range of symptoms that also vary in severity).
All that being said, I doubt that IgG testing is perfectly accurate. However, I do think that IgG levels correlate with food sensitivities in some cases - it's possible that raised IgG is a necessary, but not sufficient, condition for developing a low-grade immune response. That is to say, if you have raised IgG for peanuts, wheat, and milk, and raised [X] for just wheat, then you will only develop symptoms to wheat; the IgG test therefore informs you of all of the things you *could* be sensitive to, and thus still gives you a modicum of information that can be used to your benefit ([X] is just some other downstream factor that could interact with IgG in some manner). The point is that we don't know enough about IgG and food intolerances to assert that IgG testing is invalid. On the other hand, we have some reason to believe that it works: IgG increases in response to food antigens, and IgG is involved in the elimination of antigens.
Most tests use IgG4. I think this little gem describes what we know about it best, and itself addresses many of the critiques of using IgG4 testing:
"Finally, if antigen persists, high affinity IgG4 is produced, which dampens down inflammation by helping to curtail FcR-mediated processes." (wikipedia IgG page)
Of interest, conventional medicine has proclaimed, because of the above, that raised IgG4 means that the immune system tolerates the antigen - IgG4 is a marker of tolerance, after all, when it comes to pathogens, and you can see from that quote that it achieves this tolerance by inhibiting FcR-mediated processes. However:
"The skin and digestive tract of humans and many other organisms is colonized with an ecosystem of microorganisms that is referred to as the microbiome. Though in mammals a number of defenses exist to keep the microbiota at a safe distance, including a constant sampling and presentation of microbial antigens by local DCs, most organisms do not react against commensal microorganisms and tolerate their presence. Reactions are mounted, however, to pathogenic microbes and microbes that breach physiological barriers." (wikipedia immune tolerance page)
So if you were to eat a food, you might get increased IgG4, and tolerance would happen. But if antigens cross into the bloodstream, you would get an immune response in addition to having elevated IgG4. The [X] factor I was talking about before could well be the translocation of a food antigen across the intestinal wall, which could be increased if the intestine is damaged by pathogens, pharmaceuticals, or certain types of other foods (gluten) that interact with cells lining the intestinal lumen.
I can say that my personal experiences somewhat align with this theory. If I eat wheat, I'll get (almost) flat red spots on my chest, and they will sometimes itch. If I keep eating wheat, these spots turn into pustules that look exactly like acne. The same thing happens if I eat chocolate. If I stop eating these foods (and a couple others - soy being one of them), the skin on my chest heals and becomes flawless. On the IgG test I took, I was sensitive to wheat, soy, peanuts, shellfish, and a few others (can't remember if chocolate was on the test). I break out from most of the things I tested sensitive for, with the notable exception of peanuts (though to be fair, I haven't tested peanut extensively as I don't really eat them). I think it's likely that antibiotic use (as a child for ear infections, and then later for acne; microbes are basically a barrier to antigens that cover your intestine) as well as poor diet led to damage, which allowed food antigens to cross more frequently and thus altered my immune response to certain foods that I was likely tolerating (that is, foods for which I had raised IgG4).
Anyways, sorry for writing a book, but I've seen conventional medicine fail many more times than it's succeeded. Medical practitioners, and even the scientists doing the basic research, are far too eager to fulfill their own hypotheses with ambiguous data.