Both are used by native speakers. If you want the subject to be 'selection', then 'is' would be the verb of choice:
 A selection is provided.
If you want the subject to be 'newspapers and magazines', then 'are' would be the verb of choice:
 . . . newspapers and magazines are provided.
Grammatically though, and this what Traditonalist would like to see native speakers use, since the phrase 'newspapers and magazines' functions as the object of 'selection', it shouldn't agree in number with the verb. Only subjects agree with the verb and 'selection' is the subject.