Ah yes, prices will change by that point, also Haswell CPU's will be available by then. Best off to look at pricing a computer at the very most 2 months before you purchase but i'd say 3-4 weeks is better.
Start going to local computer shops now, get them to know your face and chat with them, that way when the time comes they'll be more willing to help out. My local computer shop is great, say i need a sata cable or case speaker or something cheap i can pop in and they'll usually give it to me free or ask me to chuck a little cash in the charity box.