[footfootfoot]

Are you looking to assemble or actually build?
Alder is in the birch family and is relatively cheap, sort of durable, and is mostly a good wood for manufacturers to use. I don't know any woodworkers who would go out of their way to buy it. It is ok.

How much do you want to spend? Forget IKEA, while the stuff may look nice it is a 5 year piece at best.

If you aren't going to build it yourself and don't want to hire a local carpenter/cabinetmaker to make it and you don't want crap, then go to EJ Audi or some other Stickley type place.

Finding a woodworker to knock out a couple of simple tables without drawers shouldn't be that hard, or expensive. I bet you could get a pair for under $600. esp. if you were willing to sand and finish them, and want shaker style which is pretty simple and un-ornamented.