Well, friends of mine are off to the states ( the Unites Ones ) next month for a few weeks, and had a while to ponder how they would deal with their communications needs whilst over the pond.
They rather sensibly acquired a Pay As You Go American SIM card and then needed a suitable mobile.
Luckily I had a spare Nokia 6230 nokiaing about which is TriBand and unlocked, its talk time is not superb, but they have picked up a car charger from ebay and an American PSU.
They will need to find about networks and call charges I suppose and calling them from Brighton will be expensive so I will forgo that option.
If data charges in the US are as cheap, comparatively , as their fuel charges I guess they will be able to access their email via GPRS as the Nokia 6230 supports this method.
The large storage space of free webmail these days, Gmail or MSN, allows them also to email themselves and store whatever planning documents, maps and information they will need whilst travelling for easy retreival via the web.