You can CLEP sociology as well -- there is an Introductory Sociology CLEP that EC will accept for sociology credits.
For the Human Growth CLEP, I am seriously overstudying and I need to knock it off! LOL!! I've used instacert.com and petersons.com, as well as a Chancellor's Lifespan guide. I'll let you know how it worked out this evening when I get home.
I'm also planning on using instacert.com and petersons.com for Sociology, and I have a TCN Sociology study guide. That'll be my next CLEP, probably in early February.
I don't know about the Humanities credits ... my two other AA degrees helped me out in that regard.