a few things to consider:
This case was in the local Denver paper awhile back and from the reporting and headline, I said "Go Tattered Cover!". However, as I've read about it, I'm not sure. The authorities are seeking evidence to support a crime (manfacturing speed). This is to support a case, NOT PROVE that this person made or sold speed. Of course, the fact that materials were in his house would seem to be enough evidence, IMHO, but that's another story.
They are also not asking for records of who else purchased these books. And they should not be. If they suspect that a specific person has engaged in illegal activity, I would support them getting specific information about this person. Like purchase records that deal with manufacturing speed.
Another interesting thing in many of the comments is that we should use cash, not allow our activities to be tracked, etc. However a few weeks ago there was a So should we profile? I'm in favor of limited profiling. With controls and oversight. And accountability. We need law enforcement, but we need law enforcement that keeps our rights in place. I hate laws that give too much protection to criminals, but there is a purpose to many of these laws. US society tends to favor allowing some criminals to go free to ensure very few innocent people are caught. Something not protected by many governments around the world. Personally, IMHO, we need to both be careful about what information we allow companies or the government to access or disclose. But we ALSO NEED to be less judgemental about this information. Is someone a criminal because he buys a book about drugs? No. Is someone a terrorist because they buy a book about encryption? No. In the US, we say people are innocent until proven guilty, but all too often we jump to conclusions about someone, often because of some journalist's story. Just because it is in the newspaper doesn't mean it's true. In fact, newspapers are businesses and need to get readers. Sensational stories sell and too often people believe they are true. A little skepticism is helpful to all of us. I'm getting slightly offtopic, but while protecting the First Amendment, we should not blanketly protect all criminals either. Assist the US lawmakers, but force them to be accountable and controlled. Just MHO, and I welcome a debate.