Can't find friend's charcter?

Are you searching for your friend in The Armory or in-game? I'm presuming the latter, but could very well be off the mark. :)

Perhaps you've misspelled the name? Missed a high-ASCII character? This is the message you receive (regardless of level difference) if the name you're searching for turns up no results.

Are you using "/who <enter name here>" or "/friend <enter name here>"?

Are you certain he's playing on a US client? It's possible he started a character on our EU realm set.

Q u o t e:
Is there a U.S. one and an Europe one by the same name?

In a way. :)

There's a US client and an EU client. Similarly, there's US-specific accounts and EU-specific accounts. Each client has its own set of realms that can only be accessed by the right account type (US accounts can access US realms and EU accounts can access EU realms).

If your friend in Denmark picked up an EU version of World of Warcraft—which is very likely since that's what would be available in most areas in Europe—and started an account with that, he'd be accessing the EU Aggramar, not the US version (which is what you're playing on).

Do you know if he only started a trial account, Tannithia?

Q u o t e:
Is there anyway for us to get on the same server?

Not presently, Tannithia.

Are you absolutely positive on the spelling of your friend's name, by the way? I've checked, and there is no player by the name of "Detech" on Aggramar. Do you happen to know his race and class (level, too, perhaps)?