You can also check out "The Barbell Prescription" by Andy Baker. This book is like Starting Strength but for the 45+ demographic. (Interestingly, Starting Strength can be used for this demographic also.)

There have been documented instances of older folks reversing degenerative conditions after picking up strength training. You're also never old enough to get stronger!

That said, finding a trainer that knows what they are doing is the fastest way to progress. I'm biased towards the Starting Strength community as these trainers undergo an intensive program before they are certified to be an SS coach (on top of their past intensive training), but there are many other qualified trainers out there.