We are leaving this fall for Ireland (4days), England (4 days) and Italy (12 days). I love my GPS on my iphone and would like to use it to call ahead a day or two for sleeping arrangements. I also want to be able to make reservations from it for sites. Is this going to be really expensive or is there a trick?
There is no trick. You must become completely acquainted with the iPhone and AT&T's roaming plans (I don't think Verizon's iPhones work in Europe unless on wifi). To minimize data usage, turn off email gathering unless you're on wifi, turn off data roaming unless you really need it, don't download maps and know how to keep track of data usage while abroad to be sure your roaming plan is adequate. If you're gong to be using the phone function only occasionally, AT&T's roaming plan isn't a bad deal.
There are some other posts here about the "danger" of using the device...look for them and read....unexpected and very high bills.
Aubrey, I would STRONGLY ADVISE that you do some research before happily web surfing your way across Europe with your iPhone! You may find it very helpful to read This Thread that was posted recently on the HelpLine. Any application that uses data roaming could potentially be VERY expensive, something that you won't know about until you return home and receive the bill. You might want to contact AT&T for information on their voice and data "travel packs", which will minimize the charges to some extent. Also, be sure you're familiar with the method to check the data usage. I'd probably leave the data roaming switched "off" unless absolutely necessary, and use Wi-Fi as much as possible. Happy travels!