Your Web site must be up and running when the prospect tries to reach it. Your product set must meet the prospect's needs at that time. And you must reach your prospect in a compelling manner before someone else's Web banner or link distracts him. Purchase or barter for links on Web sites aimed at newcomers to your prospect category. Provide a growth path into other products so you can sell to them repeatedly, even after they outgrow their initial purchase.
Prospects travel the path of least resistance.
Customers are like electrons. They follow the path of least resistance. And in many cases, it's simply much easier for them to pick up the phone than to create an electronic transaction. Allow them to order your product electronically, of course. But don't stop there.