I like my coffee the same way too, black, strong and good quality.
My personal favourite is Ethiopian Sidamo coffee, Sommerfield's Best Ever range (believe it or not) is actually the best version that I have found. It is a strong, rich coffee that is not bitter but instead leaves a wine like aftertaste in the mouth it is very pleasant. The Northern Tea company's Sidoma is also very nice but is not strong enough in my opinion.
Machu Picchu from Peru is another of my favourites as it also is rich, full bodied and strong, but is not bitter.
Forget paying Starbucks etc £3 for a coffee. Excellent coffee can be bought locally or online, bean grinders can be expensive and time consuming, but worth it. However there is also nothing wrong with buying it ready ground and done in a machine or cafetiere.