Dinny - I was a vegan but now just a veggie. I loved it but did have problems with getting B12 - not because the vegan diet necessarily lacks B12 but because I seem to have some bizarre thing where I don't absorb it very well.
I missed cheese terribly and that is the main reason I am not vegan now. I still don't eat eggs except in pre-prepared things. We all drink soya milk as I prefer the taste and also because it brings the level of dairy produce we buy down to a minimal amount. Do eat a lot of butter, though .
We still eat vegan meals most days as a family and have vegan friends round quite often. I prefer it in a lot of ways.
I think Peter Cox's books are quite good for nutrition. The health problems are really over reported and it is not hard to get good nutrition as long as you are eating a wide range of food and do a little basic homework. I would advise you to do it gradually and omit one thing at a time - ie this week find a soya / rice / oat milk that you like and stop buying cow's milk. Next week cut out eggs.
Make sure you have lots of fresh fruit in the house and interesting vegetables. Try to plan meals around vegan foods ie grains, vegetables, pulses, beans, seeds, nuts, fruits rather than thinking "Hmm, macaroni cheese. How can I make that as a vegan dish."
It always used to make me laugh when people said "Vegan? But what do you eat?" Erm, probably a much wider range of foods than most people in this country who just eat meat, milk and wheat for the vast majority of their meals.
Good luck, I hope you succeed, but be prepared for people to get very funny about it. It seems awfully threatening and most people just don't want to know about the animal welfare issues. Sorry if I have rambled on but I hope this helps a bit.