A new data resource is now available for download. It is a spreadsheet containing park factors for each team for all seasons since 1974. In addition, it breaks down the park factors into splits for left handed batters, right handed batters, left handed pitchers, and right handed pitchers.
For example, it allows you to see what effect Fenway Park and Tropicana Field had on doubles for left handed batters in 2010.
Answer: Fenway increased them by 18.4% (park factor 1.1839) while Tropicana decreased them by 10.3% (park factor 0.8973) -- look for Carl Crawford's doubles total to rise!
Download the spreadsheet here:
MLB Park Factors With Splits