Extole is a referral marketing startup that has raised $5 million in a new round of funding. Extole offers a suite of advocacy products to encourage fans to promote companies or products. Extole is now focusing on a platform that companies use for recommending services to a friend for a reward.For example, if you refer a friend to clothing company American Giant, you will get $15 off when using Extole. The campaigns are customizable and there are analytics available through the service. The platform will become available to everyone early next year. This new round of funding was provided by Norwest Ventures, Shasta Ventures, Redpoint Ventures, and Trident Capital.