Wood – What kind of board is this, and where can I get some

That is maple. Plain old, flat sawn rock maple. There's no way to tell from the pictures if its engineered or solid but if you knock on it the sound will tell you. Solid sounds very dull, like knocking on a sidewalk. Engineered hardwood, even if its installed very well, sounds a bit hollow. You might not notice it when you walk across the room but if you tap on it with your wedding ring you'll know. I might suggest not contracting with the guy that thought that was bamboo because apparently he doesn't know what either bamboo or maple looks like, which is not a great sign.

Here is the answer to my actual question:

http://awc.org/codes-standards/calculators-software/spancalc

Edit: Sorry if I'm not on the same wavelengths as anyone else. I already know about insurance and inspectors, and that was not at all what I was asking about. I just wanted to know what length of wood would span a certain distance given various criteria. I would have expected an answer to that question, instead of all the "your a dumb homeowner who's going to get in trouble" type replies. I question the idea that there will be 50psf of weight from snow given the fact that it is an almost non-solid top, and saw no real attempt to answer my question, so I had to come up with this. It took me awhile to find, and I hope it helps others.