Help required from the experts...
Can I use a flat wing or do I need to  make a proper aerofoil ...
Details of my plane
Made from 3 mm coro and fuse length 20''
Model: Avispad

Search for mini avispad...... No expert advice will be required

Didn't find anything of much use

proper aerofoils are preferred over flat wings.

Flat wings mostly have thrust to weight ratio 1:1 or more. Whereas aerofoils give better lift and glide capability and can work for <1 thrust to weight ratio.

see the wings here...http://www.rcindia.org/electric-planes/mini-avispad/msg153292/#msg153292