I have just bought some Newtons too. I was fed up with getting knackered knees from heelstriking. I have tried COUNTLESS trainers! Only thing i could run in without getting injured quickly, was the Nike Lunaracer. These are a racing flat, and have a 4mm drop which helps to stop you smashing the ground with your heel!!
I bought Newton Distance racers as I tried a pair of Motion shoes a few years back and couldn't get on with the feel of them. These new ones, are ace though!
My advice would be to try a set of the flattest shoes you can find (except Dunlop Greenflash! ). The Lunaracers really helped me sort my running out! No more shin splints, no more ITB nonsense! Make the transition to midfoot and enjoy it!
Bear in mind, DONT run on your toes! It will hurt your calves like hell! I tried forefoot running in a pair of New Balance 1064's (14mm drop!) which made my have to lift my heel so much that i couldn't walk for a couple of days without looking like i'd soiled myself! Bin the headphones and listen to your feet for a while.
Look on the Newton website too, there are LOTS of good tips and advice to look at.