If you want to write to him, please use the following address (postage for international first class letter is $0.98 for the first ounce and $1.76 for two ounces):
253 Bukit Timah Road
Because of local sensitivities, do not address him as "elder" on the envelope. The mission discourages packages but if you do send them, you may need the mission office phone number: +65-6735-6723
You can also email him at: email@example.com
He will not be able to email you back but he promises to send you handwritten letters in reply (probably takes about 2 weeks).