Looking for work and Ageism

I was made redundant a few months ago and have applied for countless jobs since then. I thought with all my years of experience it would be fairly easy to get another job but I've had no luck so far. I've had a few interviews but no offers. Most of the time I've been interviewed by people years younger than me and I think they just don't want someone older than them working for them.

I don't put my age on my CV but as I was in my last job for 17 years its not hard for people to work out my age from my employment history. When it comes to application forms most of them want you to enter your date of birth so there is no disguising your age in reality and why should I have to?

Its really getting me down now. I keep thinking that maybe I should retrain but I don't know what to do. Any positive advice would be appreciated.