SHIMANO RP1 ROAD SHOES are as simple as shoes get. Nominally £70 but can be found for £50 depending on size required. SPD cleats are around £15 but generic copies around half that.
Of course you can easily spend £450 on shoes if you want a few bells and whistles...
You might want a pedal like Llani Boy mentions with SPD cleat compatibility on one side and something flattish on the other but once you are used to cleated pedals you will never want to go back (and people usually only fall off twice). Cleats make you "one" with the bike. The bike becomes part of you. It's a marriage,etc etc!![]()