This is a feature we have considered in the past, but have purposely chosen not to include so far. One particular reason is that IP addresses are frequently not unique. AOL users, for example, pass through a US-based proxy IP address. Were you to ban an AOL user, you might inadvertently ban thousands of potential customers from your site.
Also, users with dynamic IPs (the majority) can change them simply by logging out of their ISP and then logging back in. This makes blocking IPs a time-consuming task - and it's ulimately a battle that can't be won.
By the sounds of it, the IP in question is a "bot", possibly visiting on behalf of a "shopping directory" network or similar. It can't really do any harm, and will most likely cease visiting after a short period of time. The shopping basket table in your database is "cleaned" on a 3-monthly basis, keeping things moving along smoothly. This takes place automatically, behind the scenes.
Developer :: Bluepark Solutions