There are many paths to discovering and managing your allergies. There is certainly a lot you can do on your own, including following some of the advice on this websites, and many other helpful websites.
Professional help is also highly advisable, and absolutely necessary if you have life-threatening allergies.
I have started a new section on this website: the Allergy Professional Help Directory.
For now I have just two entries, both for Ottawa, Ontario (Canada).
I encourage anyone with suggestions to contribute to this directory! Please make your suggestions in the comment section of either this article, or (better yet) the help directory section.