are ptc websites practical? how much money can you expect to get if you have many ptc accounts?

That may be one of the lowest paying, low skill tasks out there. Take care any offering more than a couple cents a click are scams that won't pay. In some cases you may be helping to rip off businesses paying prime rates for web sites ads that they expect to attract real prospects.

Develop some skills you can apply to more productive work that will be better paying. One step up may be the micro task sits like Amazon's mturk.com or microworkers.com

If you have some marketable design, programming or writing-translation skills you might find short term work at Odesk.com and Elance.com which are a couple of the biggest freelance worker marketplaces, Odesk has about 420 different qualification tests that can help a new worker with no history of completed projects to win job bids:

https://www.odesk.com/tests

Elance alone reports their (mostly skilled) workers earned $285 Million in 2013

https://www.elance.com/q/online-employment-report