I have found quite a few useful sets of co-ordinates and polars at the NASG airfoil database at http://www.nasg.com/afdb/index-e.phtml and you can find the odd actual model airfoil in there though it requires a bit of hunting around. also it isn't big on vintage designs...

e.g. here's an airfoil for a plane called a trainer 60:-
http://www.nasg.com/afdb/show-airfoil-e.phtml?id=1176

here's the same for an "ultrasport"
http://www.nasg.com/afdb/show-airfoil-e.phtml?id=1176

here's a clark y - as used on loads of aircraft
http://www.nasg.com/afdb/show-airfoil-e.phtml?id=59

there are loads of seligs and epplers here if you want to get in to sections used on models more recently...

happy hunting!