New customer profiling

We have over 1000 new customers register and place their first order each month. We need to profile the customer to confirm how we best engage with them. Many are small business's and are best left as a web account that we manage via the website and communicate with them via email. There are some that are either larger small business's and we want to make an inrtoductory call to check that they are happy with their initial order. What are really looking for are the larger organisations where we want to use the initial order as a mechanism to engage them with our senior account managers and technical specialists.