I've got core temps of 58 and 56 with CPUID hardwar mon. and both say 56 with speedfan.

The idle CPU temp is 55.

When I stress the cpu they go up to about 65-70.

Is this normal? What is the max/norm for core 2 duo temperatures?

No, I just tried that software on my E6750, both cores are 30 - 35.

My PC has been on all day and Ive been playing Crysis too.

Norm is about what you have-- max is 85C
All the hardware/OC sites say to use Core Temp--
Core Temp
sensors are not 100% accurate-- and neither is software.
It's a guide. Nothing to panic over.

You could consider adding a better CPU cooler-- and/or case fans-- to bring temps down.

I am running stock heatsink, voltage upped to around 1.338 for stability:

3200 cpu (8x multiplier)
1600 qdr
800 ddr2

temps:
-idle 54(cputin), 58, 56
-load 66, 67, 66

I was afraid to overclock it any higher. Getting it stable at 3300 meant closer to 1.4v and I don't want to get a new heatsink to compensate for that voltage. I'm happy with a 20% OC for now , especially considering my ram is running at 1:1 ratio. Unfortunately I can't bring the ram to 1t from 2t without errors. Should I pump more voltage into it? It's corsair TWIN2X2048-6400C5DHX.

You're going to blow your RAM to hell at this rate O.o.. a 1:1 ratio is extremely stressful on RAM, especially at a 20% overclock, you're lucky switching your RAM to 1T didn't fry it.

Your high temperatures are caused by the high voltage, I wouldn't let your CPU go past 70, as that's about as much as C2D can take