What can u get from them and what offers do u do? how many wat are some?
Most sites offer $50 GiftCards or PayPal, some offer other things. The ref ammounts are very high, as the offer don't pay that well. As for the offers, you basically fill out a form and submit it, or register for a free service.
I suggest the Free4me network, since the other two are kinda shady in crediting and whatnot.