Where can I find good sources which talk about House of Leaves?
Mark Z. Danielewski's House of Leaves is an experiemental novel which uses abstract and unusual typography to suppliment the story.
For information about the book itself, the eNotes study guide -- including Salem Notes and Wikipedia -- will give a great deal of help in deciphering the non-linear story. Additionally, a Google search for "Mark Z. Danielewski interview" or "Mark Z. Danielewski House of Leaves" will also help, although you should be careful to look for original sources instead of discussion and interpretation by third-party sites or blogs. Here are a few of the interviews I found with information on the book.
Of course, the best source is the book itself; it is available at most large bookstores on the shelf or by order, and online at booksellers. It is not available in eBook form at this time.
Here's a legitimate source I found in my search.
I also found some on a research database which most people can access from a library.
Honestly, you can't find a credible source for this book. Danielewski is a very reserved author, and does not give interviews. None of the references in the book are real, as I'm sure you know. Any "source" you can find on the internet is just guess work from any random reader.