A couple of links if you think you might have issues with gluten.

Some good information here.  The list of symptoms is endless and the symptoms are common to many health issues.  For me it was important to understand my set of symptoms and what triggered them over time by identifying patterns.  The ultimate clues came when my symptoms were triggered and I later found that I had in fact eaten gluten by accident.

http://gluten-intolerance-symptoms.com/

This is probably the best site I've found for information about gluten related health problems.

http://www.cureceliacdisease.org/