i have a hunch these places have their own guides who organise informative tours like in versailles.
but their websites dont mention them.
anyone here used them? any idea on their price & frequency? thanks

At Windsor you tour at your own pace and there are very well informed guides/guards in every stateroom. I would by the guidebooklet to help you get your bearings.

At HCP you can hire the audio guides - and again go at your own pace. There are also guided tours of specific areas/topics led by guides in period costume. The day's tours are listed on a board in the ticket office and in the gatehouse as you enter the Palace. But the audio tours are really good - much better than at many sites.

Windsor Castle also has an audio tour, but I don't remember if it was included in the price or cost extra. I'm thinking it cost extra, but it's worth it - you'll get more out of the tour. Same with Hampton Court.

When we went to Hampton Court both the audio guides and the human guides (in costume) were included with admission. Both were excellent. Try to take a couple of the guided tours. Questions were encouraged.

Kayb95: I think you are right - I never think of the audio guides at Windsor Castle. I've probably been there 15 or more times over the years so don't give them a second thought (heck - I think I could give guided tours by now). But I do seem to remember seeing folks carrying audio guides last June.