David just tweeted an address where fans can send mail now and while he is on mission. This is what he said:

Hey guys, so I got an address where you can send mail to now and also while I’m gone. You can send it here: PO Box 4297 Apopka, FL 32704 USA
You guys might say “Why Florida?” but my manager’s down there & people I know that’ll make sure I get it before I go and while I’m gone! :)

ETA: Please send letters and cards only, no parcels, thank you. Please address the mail to David Archuleta as follows:

David Archuleta
PO Box 4297
Apopka, FL 32704