The www.lguide.com website has been recommended several times by TrainingZONE users and it's definitely worth checking out.
The site lists a range of online courses categorised within headings including: Management, Human Resources, Communications, Sales, etc, each of which have several sub-categories.
The site lists courses from several suppliers (SkillSoft, Maxim, and others) and provides information on pricing and content as well as a review guide and star rating.
At this stage there are not too many entries, so you don't end up particularly confused. This makes searching and finding relatively easy. As the range of online materials increases, this will no doubt become more difficult.
The site also contains some helpful introductory advice about using online learning, and a range of other recommendations about books, etc.