Does anyone know where I can purchase yarn for sock that is 32sts=4" or less? The local stores are all huge and thick.
Do a search for fingering weight or lace weight and you should have some luck. Most online stores carry yarn in that weight.
My favorite place to buy sock yarn is Carodan Farm. They have a large selection:
http://www.carodanfarm.com/shopsite_sc/store/html/sock_yarns_patterns.html