You must have a current Coggins of course and a local U.S. veterinarian to certify the horses' health. The paperwork is then sent to the "Federal Vet's" office and they certify the info from the local vet and issue your travel papers.
To simplify things, I wait to get a fresh Coggin's when I am in ND from the same local vet that checks their health. BTW, this vet's mother is the federal vet and I haven't had any issues with paper work!
Runs around $200 for three horses using this methodology for me. I think it is actually cheaper getting everything done at once rather than an earlier Coggin's at home.
Incidentally, the "new" paperwork last year contained a picture of each horse and the form used ended up with all three of the horses on the same piece of paper. You go into Canada with three, you need to come out with three! Otherwise, they'll be figuring out a "tax" you owe for selling a horse up there.
The federal vet certificate is a 60 day temporary importation/visitation certificate. This allows you to go into Canada and use the horses and get them back across the border without further inspection. Stay longer and you will have to repeat the process in Canada and I've been told this is more expensive on that side of the border.