Parish registers
Almost 800,000 Bedfordshire baptisms and marriages are included in the IGI at FamilySearch but some parishes are missing (you can see the coverage here).
There are very few baptism or marriage entries for Bedfordshire at either findmypast or Ancestry, but there are 355,503 burial entries from the National Burial Index at findmypast.
The volunteers of FreeREG have transcribed over 270,000 records. To check the coverage for a particular parish follow this link. There is currently no OPC project for Bedfordshire.
Births, marriages and deaths
Registration districts in Bedfordshire
There are currently NO local indexes of births, marriages and deaths for Bedfordshire.
Pre-1841 censuses
Also consider....
Reproduced courtesy of Francis Frith.
Key Bedfordshire resources
Bedfordshire and Luton Archives and Records Service based in Bedford was founded in 1913, and was the first County record office in England (the earliest records held date back to 1166). All of the pre-1812 parish registers have been transcribed, indexed, and published in book form and as microfiche (details of cost and availability are given here). There is an online index of prisoners in Bedford Gaol which has in excess of 40,000 entries, and the Community Archives are a growing resource of local historical detail.
Bedfordshire Family History Society publishes CD ROMs with transcriptions of the registers for individual parishes (coverage varies) - full details and prices can be found here.