I'm looking to go the states for about 4 months from October, and i'm looking for ways to keep in touch with home (UK). Is it worth me buying a cheap mobile phone? Or stick to phonecards? Also, any info on post restante services in the states so i can (hopefully) receive christmas presents etc? :)

I suggest you buy a pre-paid phonecard when you arrive in the States; make sure the one you buy will do international calls. They're widely available from convenience stores in $10 and $20 denominations. To use them, dial the toll free number and PIN number given on the card, then the number you want. A recorded voice will tell you how much time you've got left. In cost per minute terms they work out very cheaply indeed.

Pete