Ok so I hope I am posting this in the right place and i hope this has not been posted already. I sent out a basic email to my guests making them aware of their cell phone options and roaming plans that are available in hopes noone gets surprised with high phone bills after the wedding.
I think this is helpful, general information that can help your guests plan and prepare.
Of course you can change the fonts, colors and formats in your email to make it look a lot nicer.
Att formerly Cingular: You can call them dialing 611 from your cell phone or by dialing 800-331-0500. Simply call an add the World traveler plan for $5.99 per month (they are also able to have the feature start and end on the dates you requested and you will only see a prorated charge for the days you have it. I would suggest adding it 1 day before you leave and leaving it on for at least 2 days after you plan on leaving just in case you were to be delayed in Mexico. This plan allows you to use your phone as you normally would, you will still incur a roaming charge but it will be .59 instead of .99 per minute, minutes will be deducted as usual. Text messages are below and also depend on the current text/data plan you already have-
Blackberrry charges can add up pretty quick - it is suggested not to use Blackberry Internet - you can keep your phone in airplane mode or turn of your wireless feature for this.
Sending Text, Picture, and Video Messages when outside the U.S.
Text Messages $0.50 per message sent
Picture and Video Messages $1.30 per message sent
Wireless, DSL Internet, satellite TV Services and Phone | AT&T
Sprint: You can call them directly 888-211-4727. You may want to confirm, but from what I understand, they have a flat per minute rate of .99 for voice calling and .20 per text message while in Mexico - there are additional text messaging plans you can add for example, 1000 text messages for $10 per month or unlimited text messages for $15 per month - call to make sure your phone is compatible and has the international dialing feature turned on
Cell Phones, Mobile Phones, and Wireless Calling Plans from Sprint
Verizon: You can call them dialing 611 from your cell phone or by calling 800-922-0204 . Verizon has a flat rate roaming charge of .99 per minute when using your phone while roaming in Mexico. Please call to make sure your phone has the international dialing feature turned on. For text messaging:
While traveling outside the U.S., the text messaging rates are:
$0.50/address sent
$0.05/message received
Cell Phones, Cell Phone Plans, Cell Phone Accessories - Verizon Wireless
T-Mobile: You can contact them using 611 from your wireless phone or by calling 800-937-8997. You want to first Call and activate WorldClass service. Charges will be $1.49 per minute - call to be sure there are no other discounted plans you can add to relieve some of these charges.
Voice rate*: $1.49
Text messaging rate
(per message)*:
$0.35 sent, $0.15 received (or pulled from feature bucket)
Internet(GPRS) rate*: $0.01 per KB in Canada
$0.0150 per KB in all other countries
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Cell Phone Roaming for Mexico 
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