Try Media.net (It's Yahoo!/Bing's alternative to AdSense). However, truth be told, no other PPC network is going to make the same kind of money that AdSense does. And if you can't get into AdSense, you most likely won't be making much money elsewhere either. (Unless it was because you got banned from AdSense for fraudulent clicks.)
As far as i know , the Adsense is one of the best PPC network because it is not only offers PPC but they also offer CPM ads. The earning potential in Adsense is much higher. However, Google is getting very strickt day by day not in terms of approving the adsense account but also in terms of paying you money.