I can't say for certain how things work down in the States, but being a certified graderman myself I can tell you what I do know. Our lumber grades up here still fall under the NLGA (National Lumber Grading Authority) rule book, which is a co-operative effort between Canada and the US, and some European and Japanese rules are even creeping their way into the system. So I presume that the grade rules and necessary training would be fairly constant throughout North America. Keep in mind that I am only speaking of softwood structural grades; hardwood finishing grades are a completely different animal and I am not certified to deal with them, and though they do still fall under NLGA rules, it's a completely different section. As for being species specific though, my grading ticket, and the most common one offered here, covers Structural Joists & Planks (2-14" wide, 2-6" thick, graded #1, #2, etc), Studs, 1" commons (tongue and groove siding, fence boards, etc.), Fingerjointed lumber, and machine graded lumber. All of these can be graded under virtually any species in the NLGA rules as long as it's included in the stamp designation. The common species groups are SPF (Spruce-Pine-Fir, but NOT Douglas Fir), Hemlock - Fir (Silver Fir, NOT Douglas), Cedar (Western Red or Yellow) Douglas Fir - Larch, and Northern Species, which allows pretty much any combination of species but greatly reduces value since constant similar wood properties cannot be guaranteed. Courses in British Columbia are tailored to suit the region though, for instance out at the coast where there are still mills that cut the big old-growth trees, they have to learn to grade all sorts of different things that I didn't, like Clear grades, massive beams and spars, ship material, moldings, etc., but maybe not studs and the like which I did.
Since I work for a mill that is a member of the lumber council responsible for training gradermen, my training was free provided that I passed the course. Anyone can take it though if they want to cough up the money, and I believe it was just over $300 for non-members when I re-examined this past February. Up here the course is about 6 weeks, two days a week for 2-3 hrs per day. I found it very easy and anyone who has spent time working around wood will find most of it very common sense. For goodness' sake, the first day they taught how to read a measuring tape!
As for hiring a grader to come and grade your wood for you, I don't know how that would/could work. I did have someone ask me to do this once, and I was stumped. I don't have a personal stamp just because I'm certified to grade, my ticket just allows me to work under someone else's. We have a couple custom planer operations in town that basically just plane, end trim, and stamp lumber for small sawmills or individuals. To get a stamp, one has to be a paying member of the lumber council as far as I know. That stamp is almost like an insurance policy, because if a company sends out a load that's stamped stud grade and the customer finds an inordinate amount of offgrade boards (the limit is 5% per load), they can file a claim or sue for reimbursement OR sometimes even force the company to pay to have the whole lot shipped back and refunded or replaced. I have no idea what it costs to get a stamp from the council, or if individuals even can, but they do represent a lot of responsibility so I can see where some of the cost comes from.
Hope that's helpful somehow. If you want any rules or specifics on particular grades, let me know. Oh, and were you wanting to use this wood yourself for something you're building, or be able to sell it to builders as construction grades? If the former, I'm inclined to agree with the above idea of just paying an engineer to sign off on the job if possible, depending on the cost and feasibility of certifying yourself.
