Another Via venue question (sorry!)

[automusicgraph]

I heard this piece of advice somewhere, but am not sure:
Should I write another short letter (in addition to my auto request) to the Venue, asking them if they will pass the letter to the artist, and put everything in a bigger envelope addressed to the venue?
Or should I just mail a request to the artist addressed to the artist with the venue's address?
Also, will the mail at a venue be checked everyday? Because if my letter is missed, the celeb won't see it!
And can I send fan mail to the address where "questions and comments" are supposed to go?
Thank you very much{up}... I won't have much time left to send it, because he is performing soon!!