If you want to get a cube to muck around with, don't frustrate yourself with something default - either pull apart and lubricate one of the standard ones, or pay a little bit more and get something used by at least keen amateurs. The cheap ones are pretty miserable to use.

I have one of these and it's smooth: http://lubixcube.com/lubix_dayan_guhong_v1.html

Bad Mephisto has already been linked elsewhere - he has some really helpful videos and a cheatsheet to refer to.