There is dried flavored coffee mate - but I dunno about coffee. I don't like the flavored stuff. You could look into getting flavored syrups - we do that sometimes!
Nacho cheese - haven't found anything too great here. Don't by the stuff in the chilled dip section, as it's usually mayo based.
Salsa - Both Asda and Tesco have some in the fresh section. It's really good, and doesn't cost as much as the fresh stuff did in the states. It's about £1, and it's delicious!
Ranch dressing - They have some at either Lidl or Aldi but it's just not even close to being the same. There is also Newmans Own and Cardini's ranch... But I think they're both gross. I make my own using this recipe!http://thepioneerwoman.com/cooking/2008/06/homemade-ranch-dressing/
It's better than the store bought stuff back home anyway, and it's quite easy.
Buffalo Wing Sauce - Discovery brand makes it. Never tried it though.http://www.discoveryfoods.co.uk/product/129/buffalo-wings-sauce.html