Take a look at "The Corehouse" down below in the vendors section. We've got or can cut just about any wing to fit any need.
Foam wings are faster and easier to build. The simplest wing is a foam panel with top and bottom spars covered with silkspan and then plastic film. A 48in. stunt trainer built this way will survive a straight in crash into moderate turf without breaking anything.
Larger planes, balsa sheeting, etc take more time and preparation. In the end they can be very close to the best built up airframes.
The most recent wing I cut was for a Windy Urtnowski Cardinal. It was cut from somewhat denser foam but hollowed out about 60%. That saves just about all the weight of the covering and finishing.
Another approach to building a bigger PA plane is the capstrip method. One of our local flyers, Dave Noll, built a series of capstrip winged planes in the 1980's that were fully competition capable. This procedure uses top and bottom spars, sheeting on the leading edge at least part way to the spars, and sheets top and bottom on the trailing edge with a rear capstrip. Balsa blocks for the hinges are buried in the trailing edge. 1/4-3/8 wide capstrips run between the leading edge sheeting and the trailing edge sheeting. The final covering can be done by any covering method desired.
It was too bad Dave just couldn't develop the skills to get into the top placings in Open class, or Expert.
Pic is a flapless stunter, 750 squares, 49ounces. 60in. span with a hollow foam wing.