Below are some of the Bloodstock sites that I would recommend.
This is a good resource for keeping upto date on international racing. It underwent a significant revamp last year and the majority of content is now taken directly from other websites. I think this has reduced the impartiality and quality of the website but it still has a very useful stakes results section.
This site is very good if you want to check a pedigree back to the founding sires. You can also add your own pedigrees to the database.
As the name suggests an Australian site but lots of interesting articles
Similar to pedigree query but also provide useful percentage stats on any given mating
General Racing Sites:
The daddy of them all. Life would be impossible without it
Great form research facility as you can watch archived footage of all the races from their racetracks.
Great resource for those who follow systems. There is a monthly subscription fee but it is worth it.
A high quality blog from Sid Fernando
Ben Aitken applies dosage theory to National Hunt racing and provides insightful reviews and previews of the National Hunt scene.
John P. Sparkman’s views on the racing world.
Useful for watching free replays of races on tracks covered by Racing UK (will require you to have a skybet account)
Comprehensive portal of Australian racing