As riz suggested Collinite 476 would be a good choice, failing that maybe look at the Jeffs range as its nice and easy to top up (just like going over your car with a detail spray) so thats very handy in the winter where you really dont want to do much more than a wash.
Your prep work is every thing a good wash, clay, deep cleanse the paint work then apply a couple of coats of a durable was/sealant and your good to go.