Kalan used to take submissions through their SubmitFunnyStuff.com website, but that site is dead now. If you try to go to it, you'll be taken to Kalan's new home on Facebook. On their page you can find updates and news, and you can see their full guidelines by clicking on the Info tab. They are still the same company -- still paying $100 per greeting card idea -- just with a new page. Submissions are taken by email now, and the company encourages writers who have submitted ideas through the SubmitFunnyStuff site to resubmit those ideas through email.
Kalan is currently looking for Valentine's Day and birthday submissions.