I was wondering if I sent requests for multiple artists in the same envelope for the Jingle Bell Ball at the O2 in December whether that would be OK or would it be best to send them seperately? I'd like to send to a couple of artists there at the same time (Lady Gaga, Lily Allen, and the Saturdays) so should I send them all at once or use seperate envelopes. Also at the top of the letter (obviously not sending it yet) do I just put
Lady Gaga, Lily Allen and The Saturdays
c/o The O2 etc.
because I'm not sure whether customer services pass this kind of thing on

Thanks!