I recently purchased a 71 280se which hasnt' been started in ten years. Could someone recommen the proper starting
procedures. Drain the fuel, change the oil, etc.

Change all the fluids, including the brake fluid. Change the tranny fluid after you have been able to run the car some. Was fuel left in the tank? This may create your biggest headache if the fuel has turned to varnish in the carb/fuel line. Don't forget the coolant.
Jim
'85 300D
'95 E320
'97 CRV

How about cleaning the corrosion off of the ignition system's electrical contacts. Also, clean your battery connectors and ground wire connector.

Would anyone else recommend a shot of penetrating oil into each sparkplug hole left to sit for a day?

Shoot, if it's been sitting that long, I'd definitely shoot a little oil into each cylinder. After letting that sit for a day, with the plugs out, I'd try to turn the engine by hand just to make sure everything turns smoothly. You don't say which engine, but I'd expect the crank bolt to be 27mm.

That socket, shorty extension and a breaker bar. Laying on your back, right side of engine, pushing up should be the proper direction. With the plugs out, it should turn pretty easy if not seized.

I'd also consider changing every belt and cooling hose (including the heater hoses) before driving it.