If you speak French, here is a very good electronic guide to Corsica with very nice pictures and a lot of useful informations:

Corsica Electronic Guide

Thanks to Ollandini Voyages for this very good guide.

This guide covers everything Corsica has to offer, from child-friendly beach resorts to severe hiking trails. Major towns, such as Bastia and Bonifacio have their main sights plotted on a detailed map and illustrated tours take the reader around the island to explore local crafts and beautiful scenery. It also provides information on: where to shop, where to eat and a variety of practical information.

The DK Eyewitness Travel Guide provides expert advice to help you plan your ideal holiday, and its hundreds of photographs, illustrations and maps give you a feel for the place before you even leave home. With cutaways and floor plans of all the major sights, markets and festivals listed town by town, walks, scenic routes and themed tours, experience the flavours of Corsica with the Eyewitness Travel Guide. Winner of the Guardian & Observer “Best Guide Books” Award and Wanderlust Magazine Silver Award for ‘Top Guidebook’.

Corsica Eyewitness Travel Guide

Corsica
One of the Mediterranean’s most accessible yet least-known islands, with some of its best beaches and most beautiful mountain scenery, Corsica is an increasingly popular destination, whether you’re travelling with one of the specialist companies listed in the book or completely independently. Walking trails, detailed town write-ups and fully up-to-date hotel and restaurant listings are complemented by frequent nuggets of insight to make this the essential guidebook choice.

What The Press Say
A great guide to the island - Take A Break

If you’re going to Corsica, this guide is a must. - Everything France

EXCELLENT COVERAGE - Homes and Gardens Magazine

Corsica Travel Guide

Very nice guide edited by Lonely Planet on Corsica:

4th Edition / April 2007
304 pages / 49 maps
Written by Jean-Bernard Carillet and Miles Roddis

* Interviews with locals
* DINE OUT with the best places to sample Corsican cuisine
* Day-by-day coverage of walking the entire GR20 and other stunning hikes
* Insider tips on driving routes, activities for kids and the best diving, cycling and horse-riding spots
* Best accommodation and restaurants

Corsica Travel Guide