There are two volumes IELTS Official Practice material. I have both on the test can prepare well. In principle, a real IELTS test is reproduced exactly as you get then presented it on the inspection in each band. To be able to simulate the test and therefore 2x estimate its points and a test run. Everything is explained very well and you get an overview of the test process and content. For the Listening test a CD is. The CD also Clips find the Speaking Test, which is always last checked. Thus, you also get an idea of what score you can expect in your own language skills and it takes a fear of the exam. In the appendix of the book you will find of course the solutions and also examples of the writing test of various test candidates with the corresponding points and you get explain why the candidate has received the points here.
These books are not suitable for someone who wants to improve his English. So if a particular test value eg for writing is needed at an English university, then these books are well suited to estimate the expected test value and possibly detect deficiencies. Warning: There just so prepare for the TOEFL or IELTS to can conjure up at a sufficient English to fast a useful test result, none of the advertised books. For this at least is a preparation time of half a year with English literature (spelling and syntax and vocabulary), many English DVDs and audiobooks (listening), learn vocabulary and especially speech training (you can not imagine how hard that can be formulated when it is not usual. Practice with a partner helps a lot!) needed.