How much does this camera cost in America?

Nikon D3100 Digital SLR camera

I just need to know because I'm getting it for my birthday, but at the moment my dad is occasionally working in america so it might actually be cheaper for him to buy it over there and bring it back, if you see what I mean. I can't seem to get access to any American websites here in the UK, I was wondering if anyone can find out how much it is in America for me, in US Dollars, thanks, much appreciated!

$587.99 at Best Buy (on sale) the regular price is $699.99. They do not say how long the sale is going on for, so it really depends on how soon your dad is here.

My uncle has one that i got him for his bday. It cost around 600 dollars

Your Dad would have to add 20% VAT to the sale price because that is what UK Customs would add when he brought it in. Some US sellers have them at the equivalent of £375 and 20% on that brings the total to £450.
On ebay right now there's a retailer in Brighton offering them at £399. See item 110658930274. You could ask around local sellers who might want to compete with that price.
Even if your dad avoided customs you would still have a camera that was not covered by UK guarantees for a saving of only £25.

About $600 new. $350 used.