The best thing for special needs like that is to go to forums specific for those softwares and ask which CPUs and GPUs work best with them. Then come back here knowing basically what you want and we can help you get it for the best price.
the first thing you should consider getting is the processor. unlike games, 3d software programs run off of the processor, so if you want really blazing fast render times, i would suggest getting this 6 core processor: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
you may get a graphics card, but make sure that your 3d program can support it, otherwise you may just be wasting your money.
when you are buying these parts, it's best to get the latest stuff so that your computer wont be obsolete in a few years
hope this helps