Web Startups with a subscription based business model

Are there any founders here who are building Web Startups with a business model to sell subscriptions (or at least a free+premium model and not an advertising driven business model)?

* How difficult was is to acquire paying customers? * What type of customers are these -- individuals or small organizations? * What kind of objections did you typically face before they signed the check? * And for the benefit of the startup community, can you describe how you acquired these customers (i.e., personal contacts, cold calling, selling at relevant trade shows, etc?).