phone contracts in the us?

[sky]

yo,

i'll be touring the world soonish and will be spending a fair few weeks in the
us while at it, so i need a cell number or something over there. i could use
my current one, but roaming kills me, seeing as 4 hrs talking in london to
someone else in london with my german card cost me damn near 200 euros,
i thought it might be convenient to just get a new american card to put in
my phone, which btw is a tri-band sony k750i.

so what options do i have. oh and if possible i'd like one card to work in all
places. i'll be in new york, californication and finally hawaii. oh and what
would also rock would be low rates for calls to european countries from inside
the us with that card.

any ideas? or pages where they compare the tarifs of individual providers?

or maybe prepaid stuff, like put 50 bucks on the table and get a card with
good rates and all?

[Eagleclaw]

heck you could just buy a $25 cell phone (would include some free minutes) and put prepaid minutes on it, plenty here to choose from.