I can help with Canada too, at least the providers whose cards I can get in my area (Saskatchewan). I can get Fido, Rogers, Telus and SaskTel and presumably Bell cards. The first two of those are GSM. The rest, well, pretend I didn't mention them.

CA: SaskTel, Wind postpaid; Rogers, Bell postpaid iPad flex plans; US: T-Mobile postpaid data, prepaid voice; PureTalk (AT&T MVNO) prepaid voice/data; AT&T prepaid iPad plan
Hardware: Too much but notably iPhone 5, iPad Mini Retina LTE, Moto G LTE (N.A. version), iPhone 4. All unlocked.