Both my Chiropractor and my best friends podiatrist highly recommend them. They say NB are the best shoes for your feet. I have two pairs of their walking sneakers and I've been thrilled with them.*
Some nutritional supplements may help with the muscle pain**. You might want to try calcium and magnesium, as well as some of the others listed
here. Valerian root, an herbal remedy, is often used as a mild muscle relaxant, and may be helpful. Of course hot baths in the evening can be very soothing.
As for training the only thing I can think of is to do more sessions in shorter bursts when you are not at work, which will help your body adjust better to all of the walking. Other than that you will just end up adjusting to it over time, painful though it may be. x(
Best wishes, both with the new job and with getting over the pain.
*However since I've taken up formal exercising again I've found I'll likely have to get some custom orthotics to address some supination I've had for years, which is a separate issue.
**Standard disclaimer that this is not official medical advice, nor is it intended to prevent, cure or treat any disease, etc.