As a practicing Professional Engineer I can attest that the tried and true industry standard for the civil PE Exam Study Guide is the Michael Lindeburg, PE reference manual and sample/practice problems. If you are serious about passing the exam the first time buy this book and work through it. I also recommend highlighting and tabbing the book in a way that speeds your reference giving you more time for difficult problems.
Although it is very expensive I felt preparred when my exam day finally arrived armed primarily with these books. This manual, now in its 15th version, is a testiment to its enduring quality. In addition to the exam it may be useful for future professional reference. I loaned my book to another engineer taking the exam 6 months behind me. To get the most out of this manual I recommend you enroll in an evening PE Exam refresher class at a local university. It helped my nerves a little if nothing else with the peer group support, class Q&A discussion.