Leo, congratulations on finishing the book! I would very much appreciate a copy of your Excel spreadsheet, if you're still willing to make it available for download or by e-mail. I could also host the spreadsheet and any other materials you're willing to make publicly available on my website. Please send me a PM if you're interested.
I started working my way through JfE in January and covered the first 4-5 chapters over the course of several weeks. I put the vocab, example sentences, and some of the exercises into Excel and, ultimately, into Twinkle for review. I also enlisted the help of my wife, who is 二世, to record audio flashcards (E-J) for me. I agree that it's a good book and that it covers more in under 400 pages than other textbooks cover in multiple volumes.
However, I recently discovered the website, http://www.alljapaneseallthetime.com/blog/
, which has changed my approach somewhat. The guy who writes this blog learned Japanese to fluency - to the point where he could read technical materials and conduct job interviews in Japanese - in 18 months by reading lots of example sentences. His main tools were a dictionary, real Japanese media (internet, DVDs, manga, etc.), and a Spaced Repetition System (he used Mnemosyne). (He also recommends Heisig's RTK1 as a prerequisite, by the way.) I simply can't argue with the success he's had, so following his example, I've put JfE aside for now in order to focus on RTK1 and then, example sentences.
I do think that JfE provides a very solid foundation in grammar (probably to JLPT 1 or 2 level, though I don't know for sure), and I think that once I finish RTK and start putting example sentences into an SRS I may use the book as a source of example sentences.
As for the JfE audio, I found a copy at my local Half-Price books, and I also found a copy at an Australian used bookstore on the web. There are only four cassette tapes. As far as I know, CD's are not available. The tapes include the dialogs, listening comprehension exercises, and reading passages. The tapes, like the book itself, are well-made. However, there are only 4 of them, so they're just a supplement to the book. Other sources of audio input are definitely required.