Centennial Technologies' 1996 10-K SEC filing is worth a look, in terms of a basic case of accounting fraud. Check out the ballooning Sales, but Accounts Receivable are increasing year over year. Essentially, they're booking sales, but not getting the cash for it, so the Cash Flow is way negative. Cash Flow is so bad, Centennial hit up the market with another IPO because they needed the cash. And the market bought it (stock price went from $4 to $36).

Lawrence Cunningham wrote up a good overview on accounting fraud from a lawyer's perspective. And there's an incomplete run-through of accounting tricks.