We use large, commercial third-party registrar companies to do this. We try to find the best value offers on the domain name market and the only additional charge is for the small amount of time taken to accomplish this.
Similarly, with hosting your website, we use third-party commercial servers with high degrees of availability (better than 99.7%) and with tailored levels of service and cost - from basic value hosting, right up to enterprise hosting and secure (SSL) servers.