Any recommendation for AM3 sockets?

[DKYang]

Since I'm finally on my break and have some time. I want to try overclocking. This will be my first time. I've read all the guides out there and such. I just need your recommendations.

My specs are in my sig. My budget is $40 dollars. I prefer that Superbiz/Ewiz has it instock since right now they have a 15% off coupon and I plan to buy 2 Samsungs hard drives from them also.

These are the ones that I'm currently looking at.
ZALMAN CNPS10X
Scythe SCKTN-3000
ZALMAN CNPS9700

Which one do you think is the best out of the three? If there is a better one in my budget, then what is it?

While I'm at it, what type of thermal paste do you recommend?

Thanks for any help.

EDIT: Seems like my sig isn't showing.

AMD Athlon X4 II 630
GIGABYTE GA-MA785GMT-UD2H
Crucial 4GB DDR3
CMPSU-520H PSU
Cooler Master Storm Scout Case