When I was assigned an ex-pat position in Europe, I bought a bookshelf full of travel guides. The Eyewitness series attracted me because of their colourful, graphic pages. Now that I'm here and actually using them, I confess I find them actually useful. I am able to plan excursions, get rates (using the provided phone numbers) and such. Of all the ones I bought, this series is the one I come back to over and over again.
Look for their Paris book for more specifically on Paris. The Great Britain book is good as well. I would also highly recommend the Michelin Green (& Red of course!) Guides.