The government Innovate Blog has published some raw data from the Department for Transport, giving the location of accidents involving pedal cycles which caused personal injury and were reported to the police, for the years 2005, 2006 and 2007.
The source data is in the form of an Excel spreadsheet containing Ordnance Survey grid references, but others have reformatted and repackaged the raw data into open and more useful CSV and KML formats. The Times Online Labs Blog has a mashup of the data with Google Maps, allowing you to zoom in on your (or any) area, road or route to see how accident prone it is.
Unfortunately, the data only covers Great Britain, there are no reports for Northern Ireland. The data also does not indicate whether a cyclist was injured or caused injury to someone else, or the severity of the injuries sustained. But it is interesting nonetheless.
Further information on road accident statistics can be found in the Road Casualties Great Britain (2007) and the PSNI Road Traffic Collision Statistics (2006) reports.
We truly need something like this for Ireland as well.