David Guetta has been a fan of Mixed In Key for about 5 years. He wrote a nice testimonial for us, and I think you might be interesting in this: We just published a book about DJing that describes many DJ techniques used by top DJs like him.
The book has a lot of information for professional and beginner DJs, and it is free to read online. The hardcover will be in stores soon.
You can read the free version here:
If you're an aspiring DJ, please check it out and share with your friends!