Go for Core 2 Duo... Its way better than anything from AMD... E6600 is an excellent processor which you can get for 10K... The beauty of these processors is that you can easily overclock them to much higher speeds ( and thus performance) with stock cooling... Even without overclocking the performance of this processor is at par if not better than 6000+....
For a mobo u can go for the latest P35 based boards; since they support penryn ( which have not yet been released in the market and offer even grater performance than the present proccys) you only have to change your proccy in your next upgrade.... Am not sure of the prices though....
Else, u can go for the MSI P6N Sli Platinum Motherboard.... Check out the MSI website for its features... U might get penryn support on it too, but dont count on it...There is no official confirmation for the same...U can get one for around 11K... U can also check out the 'non-Platinum' version of it.... It retails for less than 10K...
So an E6600 + P6N Sli will cost you less than 20K....And thats a killer combo...
Hope this helps...