If you were somewhere in western Europe, I would have answered PRINCE2. But since you are in North America, here are the options that you can following as an alternative to the PMP certification:
- You can follow a course at your local school. There are lots of local schools that offer Project Management courses for a reasonable fee.
- You can pursue a Masters in Project Management at your local university.
- You can following the Project+ certification from CompTIA (of course, this certification is not even remotely recognized as the PMP)
- There are also some other (and not very popular) certifications such as: CPM (Certified Project Manager from the IAPPM: International Association of Project and Program Management), and APMC (Advanced Project Management Certification from the IIL: International Institute for Learning)