How do I know which servos?
 

So I buy a plane. Then I need a radio and servos.
So if I buy, say a Futaba 6 channel kit that comes with servos. Will the plane instuctions tell me if I need, micro, mini, or standard servos.

Or is there some other "rule of thumb"?

Does Size REALLY matter?
 

Almost ANY plane you buy will recommend servo size. Be it standard, Mini, Micro, Heavy Duty, or a combination of the above.

What type of plane are you looking for/at? Do a search here on that craft, chances are you'll find some input or can pose a question.

If your getting a trainer (.40 - .60) you'll be okay with standard servos. Park flyers require (most of the time) minis or micros, and larger aircraft/stunt birds require heavy duty servos on the elevator/ailerons.

BUT, the plane specifications/requirements should give you a good indication of what is required as a minimum.

How do I know which servos?
 

Backwing,

You'll hear it a hundred times here and as a newbie, I can attest to the fact that it's good advise - find a local club call them up they will let you know who does instruction and find out from them what kinds of radios they can "buddy box" with for instruction purposes.