I haven't heard of pear wood being used for wooden rims, but that doesnt mean they don't exist. Most commonly used wood for rims seems to be beech wood. In the 80ies there also was a company around that made mahogany rims.
Yes wooden rims are still available, check
http://www.cerchiinlegnoghisallo.com/
i own a set of their racing rims, they look very nicely made to me. I haven't laced them in, yet. They will be built with some C-Record high flange hubs and all black Veloflex tubs to complete my Mike Appel.
Martin