Everyone knows that age discrimination is a crime, but not everyone is willing to take their chances testing an employer's commitment to non-discrimination at the risk of losing out on a job opportunity.
The fact is that an employer can get in trouble for even asking your age. The best way to deal with this issue is by not dealing with it at all. Leave your age off your resume. If you feel that your extensive work history gives indication to your age, remember that a resume doesn't have to contain every single job you ever held. Only positions held during the last twenty years are relevant. You can also use a functional resume to accentuate your abilities without offering specific timetables.
Many online resources and job recruiters offer resume advice to those entering the workforce after long periods of time, as well as help finding career opportunities.