What are some alternatives?
Ambassador - Referral Automation, Made Simple.
LeadPages - LeadPages™ Software is the world's easiest landing page generator. It's the easiest way to build conversion optimized & mobile responsive landing pages.
iDevAffiliate - Extend your current sales force by creating your own army of Affiliate Marketers
Unbounce - Unbounce lets marketers build, publish and test landing pages without IT or software. A/B testing and lead gen make it a powerful marketing tool.
LinkTrust - LinkTrust is an affiliate tracking, lead generation and performance and digital marketing software.
Instapage - Backed by award winning design and the largest community of conversion marketers on the planet, Instapage builds tools that make landing page marketing easy.