The Good Pub guide can help you folks out. Gastropubs are all the rage now... must just get away from the cheap and cheerful Wetherspoons type.
Rick Steins Food Heros book also can point the way to some lovely delis, dairys and fishmongers.
Key with fish to to find a reputable fishmonger and also buy local. Granted some of you have it harder than those of us in Cornwall and Devon. As for shrimp -in most cases if you look at where they are sourced in places like Sainsburys they are coming from Indonesia and places like that. Which is exactly where many come from in the USA as well.
You can get specialty seafood but you will have to pay for it -but that's like any place.
There is quite lovely food here and quite diverse as well. Have not had a problem finding anything here in Plymouth or in my adventures in London. You just have to look harder, be willing to pay more or drive longer distances.
Now granted none of this has anything to do with Taco Bell, but I will leave the love of Taco Bell to those that actually like it. I OD'd on it in college and have not eaten it in over 5 years. Though now I think I shall have to make TexMex tonight. Found pintos at Sainsburys and black beans so I am happy.
PS I do love having a Subways!!! Also the UK Tesco whole nut peanut butter is very much like the Smuckers Natural in the USA. It's what we ate in the USA so we were happy to find it. Honestly you get used to the taste of real peanut butter without all the additives. We did. I used it to make peanit butter cookies and it was ..... orgasmic......Our Sainsburys carries the Skippy as well.