I will be staying in Camps Bay for 6 or 7 days in March 2017 and wondered if anyone knew of a company who do organised day tours of the Cape winelands from Camps Bay?
Many tour operators offer this , wine flies is one such operator that seems popular on the forum , best is search trip advisor and see which company matches your requirements.
if you don't mind waiting until your arrival , you will find a tourist booth outside the Bay Hotel, Camps Bay. I did notice wine tours being advertised last year.
Although I have no personal experience of this tour operator, Hank, the owner, is a regular poster on this forum and receives good reports also from Trip Advisor tourists.
In addition to the above, here is another option - I was checking out AirBnB last night and there are some great "City Host" immersion experiences noted. I have not done any of them so cannot formally comment, but, it may be something to look at.
Also, consider doing it yourself - hire a car, and drive the magnificent areas. Its far more fun and you can go to where you would like to go.
You can see some of my posts here on what to do in CT, and about options for wineries.