Reddit mentions of The Bounds of Sense: An Essay on Kant's Critique of Pure Reason

Yes. Trust me when I say that you'll need second literature if you are willing to understand one line of, for instance, the Critique of Pure Reason. There are good introductory books on Kant out there that can help you.

If you know almost nothing about his philosophy, I recommend Scruton's or Wood's books that approach his whole philosophy without any details, making it accessible. A good start. At the same time you could give the Prefaces A and B, and the Introduction of the first Critique a try.

For what I call "intermediary literature", there is Gardner's "GuideBook", and having "A Kant Dictionary" by your side would help a lot.

Some might recommend Allison's defense of Kant's Transcendental Idealism, I think it is great, started to read it some weeks ago, but as well as Strawson's The Bounds of Sense or Heidegger's Kant and the Problems of Metaphysics, it is way advanced.

The most important thing is that you (or any other who is reading this and is also interested in Kant) are motivated, that you don't quit when read at the first time and understand barely nothing. With effort and persistence it gets better.

p.s.: I do not intend to advertise for Amazon, you can read the synopses and reviews and buy somewhere else.

Use a good translation: http://www.amazon.com/Critique-Reason-Cambridge-Edition-Immanuel/dp/0521657296

Try out Allison (as well as Guyer's) commentaries.

Also check out a good Kantian dictionary: http://www.amazon.com/Kant-Dictionary-Blackwell-Philosopher-Dictionaries/dp/0631175350 (since much of his conceptual scheme consists of neologisms).

Lastly, you should check out Strawson's essay' The Bounds of Sense.' http://www.amazon.com/The-Bounds-Sense-Critique-Reason/dp/0415040302. It's sort of a modern 'take' on Kantian themes (not an exegesis of Kant, but a modernization of some of the arguments. It actually sheds some light on Kant's project).

And good luck, try not to be discouraged. I've had two graduate seminars on Kant and they've both been difficult. But, it's not just nonsense. There is some agreement about the structure (and importance) of many of the arguments in the critique and they're worth grappling with, even if you're dealing with reconstructions of the arguments from commentaries.