An excellent question. I like to get a free CD too and I also look up recommended sites that offer free online material like this digital learning site: www.eduation.vic.gov.au/digilearn and and these mindmapping sites at: www.mindmeister.com www.mindomo.com.

Your examples pretty much covers what I wanted to put down 1. Voice, sound samples (male or female if possible); basically a CD 2. Full of exercises and drilling that's the only way to get it into your head which would make it easy to retrieve later. 3. Practical usage 4. Possibly some referrals to some good websites like this one! haha

For teaching material: Multiple teaching methods (Graphics, reading, examples, study materials; not everyone learns the same way) Interesting content Good and realisic examples that won't confuse people Appropriate learning curve Emphasis on audio and conversation

if I buy some language books, I think these are very most important things to me. 1. The books is not too difficult to understand, and they must be very imteresting, for example, there are many pictures in the books, the words are very humour, and so on. 2. There are many things about real life in the books, and then I can learn from it and use it into the reality, for example, the sentences are used when the foreigners use in the public.. 3. At last, I will select some bookds about history, novel and so on. But they are not very difficult.

To me if it is for learning English, I will take into consideration the following details: 1. Does it suit my current language proficiency? If I am only intermediate in English, then a book at upper intermediate level would be better. Cause too advanced books might confuse me. 2. Is the book well-structured? A good book with good structure will help me learn easily and quickly. 3. Is it for practical usage? I would love to buy one book with knowledges I can use in my work or study. Actually having a CD or not is not the key factor that will decide my purchase intention. I can get plenty of MP3 files to download online.