ALiverpool: Food recommendations in Liverpool?
The London Carriage Works is wonderful. Get reservations before you go! Cuthbert's Bakehouse is affordable and good.
ALiverpool: Recommended itinerary
Beatles: If you only have one day, sign up for one of Jackie Spencer's Beatle tours. http://beatleguides.weebly.com/ She is the best guide(and has the certifications to prove it) and knows other great venues and events in Liverpool to boot.