RE: where can i get the good stuff
most supermarkets in the uk will supply quality foods, oats are always good for your carb intake with fruit and veg.
local butchers and supermarkets again will be able to offer quality protein sources and fat can be sourced from fish nuts seeds and oils.
if you struggle to go out some of the larger supermarkets do home delivery with online shopping which may help if you havent been out for 8 years
hope you manage to get your diet sorted mate and feel free to post what your currently doing for some help