Out of all the paper trading sites out there WeSeed has to be the most “newbie friendly” .
If your looking for a site that is just a step up from WeSeed there is Duedee (http://www.duedee.com
Its just as slick visually but its geared towards people who are not completely new to the markets.
Also there is the trusty stand by of Investopedia (http://simulator.investopedia.com
). Its not as pretty as other sites but it still very functional and user friendly.
Finally if you want the closest you can get to the real thing try thinkorswim’s paper trade (https://www.thinkorswim.com
). Thinkorswim is a real trading platform that offers a free demo account with which you can do simulated trades with real streaming data. The learning curve is very steep.