You can get books from Lexus Dealers or u can buy a CD from Lexus. I think there 4 volumes of the book. If i remember correctly, its about 30-40 each book.
Subscriptions are $50 per month or $350 per year, and all files are in PDF format. All Toyotas & Lexi manufactured for the US market since 1990 are included and there's a wealth of information, but it ain't cheap.....
TTE (Toyota Europe) may have something similar for the rest of the world.