Hi Kathryn,
Sorry for the delay in getting back to you. Unless your stereo amplifier has an optical input (still pretty rare), what you're looking for is a TV with a pair of stereo RCA outputs, which the Samsung LE40B550 does have.
As a side note, a telly without stereo RCA outputs could still be connected to a stereo amp by using a 3.5mm-to-RCA cable between the TV's headphone output and the amp's standard stereo connection, but that isn't as neat or effective as the method detailed above.
Hope that makes sense. Shout back if not!