After some reading (http://forums.digitalpoint.com/showthread.php?t=1613026) maybe you would like to consider Dollarade's CPA Network
As there are lots alternatives and I did not test all of them but I have heard leadbolt and affiliate cash pile is a good network you may work.
With finding alternatives to other sites. I don't think people should be telling you the BEST affiliate network. I believe people should recommend affiliate networks. Check out sites at: http://www.affiliatepaying.com/ "Trial and Error".
You can go to sites like http://cashbackaffiliates.com/networks/, http://afiliatepaying.com, etc and read reviews of other gateway sites. There are several out there and each has its distinct "feel" -- so read up on them and decide which you think might suit you the best.
Or you can just go to www.offervault.com and check which companies are paying high? I often use that site