I am not alone in thinking that the Collin’s Bird Guide is the best field guide to support the serious birdwatcher. The illustrations are excellent and it covers every bird you are likely to see in UK. A beginner would be wise to start with a UK specific guide rather than Europe-wide.
The iPhone App (Android also available) is also excellent and worth investing in so that you always have the guide with you. The ability to search by location and season is great for narrowing down potential birds too. As is the ability to play songs and calls to try to work out what you are hearing.
Thoroughly recommend.
Wild Scot 