Travel Technology - E-Mail Address For Different Cell Providers

As this (http://www.flyertalk.com/forum/11915464-post3.html)message correctly notes, you can send a text message as an e-mail to a Verizon customer by using the format [telephone number]@vtext.com.

What are the domains for AT&T, Sprint and T-Mobile?

AT&T Blue: #@mmode.com
at&t Orange: #@txt.att.net
Sprint: #@messaging.sprintpcs.com
T-Mobile USA: #@tmomail.net (some old Voicestream accounts: #@voicestream.net)

Full list: http://en.wikipedia.org/wiki/SMS_gateway

T-Mobile is @tmomail.net

http://www.google.com/search?hl=en&q=email+addresses+for+cell+phone+providers&cts=1249711078576&aq=1&oq=email+addresses+for+cell&aqi=g2

If you know someone's cell number, is there a way to find out who the provider is (besides asking them)? Maybe a place to lookup based on area code & exchange?

Yes there are places you can do this, however because of number portability the information is not always accurate. When I searched my number it showed my carrier as "New Cingular Wireless" which is now ATT. However I switched my number to yet another company.

If you google your phone number you will find several websites that will sell you information on that number. Some of these sites will tell you free if the number is a landline or cellular, and who the carrier is, but as mentioned before it not is always accurate.

If you know someone's cell number, is there a way to find out who the provider is (besides asking them)? Maybe a place to lookup based on area code & exchange?
tnid.org will give you the current carrier.

Most of the sites out there, as noted by ctuttle, aren't accurate as they only contain original carrier info, which, due to number porting, is of minimal use.

Would anyone know for DTAC in Thailand? Dunno if they offer such a service, but, in the past, finding out has been beyond my skills...