Dividend payouts (and stock splits) may be found on the Historical Prices section of Yahoo! Finance. NASDAQ also has the Dividend History page which is searchable by ticker symbols.
Dividends paid and anticipated for about 1,700 companies are available in Value Line and Value Line Historical Reports (Rutgers-restricted Access)
The Standard & Poor's Stock Reports (DANA Business Reference) and its companion, the more selective S&P Stock Market Encyclopedia, (DANA REF HG 4921 .S68) provide ten years of dividend information.
The Mergent Handbook of Common Stock also has dividend payout information for 8-10 years. (CAMDEN, DANA, CARR REF HG 4905 .M815)
Sometimes, the Wall Street Journal or the New York Times carry news of firms repurchasing shares. Consult the Newspapers Research Guide.
The cost of repurchasing shares is reported in the cash flow statement within a corporation's annual financial statements. Mergent Online (Rutgers-restricted Access) will provide up to 25 years of data.
You can also compare the number of shares outstanding over time by consulting the sources listed above for dividend information.