For turnkey where you don't have to do much work and don't have much freedom, go with either Hostedtube or Smutnode as already suggested.
If you want freedom to add your own content or use sponsor hosted content (and create other sites than tubes too), you can use
easyXsites as your free adult host. We have a
PlugRush integration so you can easily populate your tubes or blogs with top-paying banners and utilize the built in trade system to gain traffic.