HOW DO I ATTACH A PHOTO INTO A TEXT MESSAGE ON THE IPHONE 3G?

Unfortunately you can’t. That is the one drawback to the iPhone, you cannot send or receive picture/video messages. No one seems to know why. I contacted customer service and they didn’t have an answer either.

Until the iPhone gets some antivirus software on it, you will not see MMS (picture messaging) as a part of it due to the fact that someone could send you a MMS with a virus and you do not have the ability to accept or decline it so it could do nasty things to your iPhone.
Every phone that can do MMS can send them to an email address versus a phone number so I would tell your friends and family to send to an email address you have on your iPhone. I am also going to list some email formats so that you can send pictures to other cell phones. Every cell phone has an email address attached to it even if you don’t realize it.
Altell : <10 digit Number>@message.alltel.com
Amp’d Mobile : <10 digit Number>vtext.com
AT&T: <10 digit Number>@mms.att.net
Boost Mobile : <10 digit Number>@myboostmobile.com
Centennial Wireless: <10 digit Number>@myblue.com
Cingular (AT&T) : <10 digit Number>@mms.mycingular.com
Einstein PCS : <10 digit Number>einsteinmms.com
Nextel : <10 digit Number>@messagin.nextel.com
Sprint : <10 digit Number>@messaging.sprintpcs.com or <10 digit Number>@pm.sprint.com
T-Mobile : <10 digit Number>@tmomail.net
US Cellular : <10 digit Number>@mms.uscc.net
Verizon Wireless : <10 digit Number>vzwpix.com
Virgin Mobile : <10 digit Number>@vmobl.com

You can not. The iPhone uses SMS (Short Message Service) while pictures and videos can only be sent and recieved through MMS (Multi-Media Service). If you know the network of the person use this…
http://artoftheiphone.com/2008/05/10/how-to-send-an-mms-text-message-picture-with-your-iphone/

One of my qualms about iPhone. You just gotta email pics directly. That’s one of the reasons I switched to a Samsung Propelhttp://hubpages.com/hub/My-iPhone-is-Now…

AT&T is currently blocking MMS from being added onto the phone via bandwidth restrictions. Until they lighten up, MMS will not be on the phone. Hopefully the Verizon rumor is true.

Emailing them is your only option. Folks are hoping that this will be fixed in the new iPhone coming out this summer but there are no guarantees.

The only way to send photos with an iphone is to attach them to emails.

iPhone does not support MMS messaging.
you will have to email it.