Computer Security 4 stand-alone computer

In short, this question relates to securing a personal computer that is being used for business. I have the task of proividing orientation to startup business owners. The computers that these new entrants to the business world are usually configured like home computers with Win95 or Win98 or WinME. I do not consider these OS very secure. I would like to know if there exist a publication or discussion that addresses the concern of securing a computer that is not supported by the security benefits of a network and network servers?