Needles
Anyone know what kind of needles A-Trak uses?
Probably Shure M44-7 carts. Are you a heavy scratcher? Are you using a DVS or just vinyl? They’re great carts, I use them myself. But there are cheaper options out there.
I want something to scratch with, but also a sound for clubs
You could use almost any cartridge carried by guitar center or your local store. just about any would be ok in a club environment. What do you mean a sound for clubs? Do you mean just mixing in a club environment? That opens up to even more possibilities.
http://www.needledoctor.com/Shure-SC35C?sc=2&category=380
I used those carts for about 8 months before I picked up a pair of m44-7 carts.
Don’t limit yourself to the products that your favorite DJ or producer uses. It comes down to your budget, and what is best for your needs.