Finding out what stallions are standing and where can be a frustrating chore whether you are looking in North America or most other countries where standardbred breeding is conducted. In North America it is only in the past two years that the registries in the U S and in Canada have made any attempt to provide such information. I can take some credit for their efforts since I have badgered them both about providing this very necessary service.
The USTA has recently added some functionality to their listings by including some additional data for their STARS list, which consists of stallions belonging to farms that have paid them for the priviledge. The "A" list totals a little over 100 of the 700+ stallions in service in North America. They also have a basic list of other stallions in the United States with minimal information and some notable errors and exceptions. No listing of any stallions from Maine or Michigan for instance, and according to the USTA No Pan Intended still stands in the US not at Tara Hills in Canada, and Pro Bono Best, who left last fall for the UK is, according to the USTA list, still in Indiana.
Standardbred Canada's efforts are similarily inconsistent and incomplete. Their stallion list gives little more than the stallion name, contact information and fee. Stallion owners can submit this information themselves but if they want any extras such as a hypothetical mating function it costs extra. There are no stallion stats, no stallion pedigree or any other data available other than what you can get through their "pay per view" Trackit service. The USTA at least gives the top ten performers of their "A" list stallions as well as pedigree information and the option of a photo of the sire.
It seems to me that stallion information, presented in a consistent and comprehensive manner is an essential service to the breeders that both organizations purport to serve.
Some states and provinces publish stallion guides and the best ones that I have seen are Maine and Ontario although both have the disadvantage of coming out well into the season due to nomination deadlines and print delays.
Internationally the best stallion directory available is likely the French "Annuaire des Etalons", with full colour pictures, some quite spectacular, and comprehensive information on both the stallion and the farm. Some countries have online directories such as Denmark, and Australia, like Canada, offers a complete list of all stallions, but in contrast gives you much more detail on a click thru basis.
Since its inception in 2003 the PedigreeGuru website has contained a stallion and farm database which I update annually for the dozen or so countries from which I can get information. The information available to me is, as you can imagine, inconsistent and full of errors and ommissions despite being provided for the most part by the breed organizations themselves.
If you have a stallion directory for your country, state or province I would appreciate getting a copy or the online link to the information.