Right, I better say something here. First of all read a book - Born to Run.
I have been heel striker all my life (34) until last September when my wife asked me "Are you landing on your heel or fore foot?" She has just been reading Born to Run at that time...
To cut the story short -try to heel strike with bare feet - you will soon stop as it hurts too much. This is not what humans are "designed" for... Modern shoes have introduced a generation of heel strikers like myself but this is easy enough to change. 6-12 months is nonsense but take it easy initially and you should be converted in about 1-2 months.
Buy yourself minimalistic shoes like Merrel Trail Glove and start easy - you can't get it wrong because its natural. Start with 400-500m once a day on the grass and then gradually increase...Try some drills - plenty on youtube (search for barefoot running)
It took me about 1 month to convert from heel strike to fore foot (able to run 10k no problem) and I am about 10% faster, it is 100% more pleasure and fun so I put my old thick heel shoes to the bin pretty quick.
Forget about heel strike honestly, its all wrong and you NEED to change this.