That's in the range. But you don't need to spend $320 on a GPU for Photoshop. But since you'll need that cash for Windows and it's not bad. But until SuperStricker comes back with any information there is little point.If you really want to build, I suggest you read the Tom's Hardware system builder marathon articles - they put a lot of work into determining the best PC you can build for your budget category:
E.g. best $750 PC: http://www.tomshardware.com/reviews/build-your-own-budget-gaming-pc,3780.html
And as per other comments here, you don't save a huge amount of cash by self building - it's more about the enjoyment of the process. Buying used stuff will save you a lot more money (components don't really wear out like they used to), but you'll need to knowledge/research/patience to match the bits correctly.