Well if you're not able to contact him through e-mail then obviously phoning is the only other sensible option - what other way were you thinking? Carrier pigeon?
I myself prefer to do most of my contact by e-mail as it enables me to put down exactly what needs to be said and I have a record of the conversation if I need to refer back for orders etc. (plus mobile recepton in this area sucks and people can't usually reach me). However occasionally a phone call is needed so do the appropriate digging and give him a call - the worst he can do is not answer, in which case you're just as you are now.
Does he owe you something like an exchange/refund? If he does he could be avoiding you. I'm not aware of him being a forum member here so your options are limited.