There are three different tours of the chateau, when we arrived later in the afternoon, we just missed Tour 1 in English and there were no more listed, we didn't want to do Tour 2 and Tour 3 which I would have liked to go on wasn't listed at all. So we decided to do Tour 1 in Czech, we had to buy an English pamphlet explaining what each room was. As with the two other castles we visited earlier in the trip, the English language tours were more expensive, it was 125kc in Czech, 190kc for English. The Czech guide was obviously giving a lot of information, I don't know how thorough the English guides are but I think it would have been worth paying the extra few dollars if there had been an English tour.
Tour 1 covers the rooms of the South Wing, including the hunting hall and several salons and bedrooms
Tour 2 covers the rooms of the North Wing, including the chapel and the armoury
Tour 3 covers the personal apartment of the Archduke and his wife, the shooting range, St. George's Museum and the glasshouse in the Rose Garden (200kc for Czech, 300kc for other languages)
The room that we visited on Tour 1 that was the most memorable was the hunting hall, the walls lined with hunting trophies, deer antlers, stuffed badgers, fox, birds. The archduke appears to have kept meticulous records, it's estimated that he hunted down 275,000 animals, just a small fraction of which appear at the chateau, the plaques all marked with the date and place that the poor animal met it's untimely end. Maybe there's a karmic twist to this story since the archduke's end came when someone hunted and killed him, I like to think that it was a reincarnated badger.
The attached website has a little information in English but if you want admission prices and opening hours you have to look at the Czech language section.
Konopiste is well marked from the highway, it was easy to find the parking lot with a charge for parking of 60kc (around $4US). From the lot you can get to the chateau by motorized tram, I believe there were also horse drawn carriages or you can do it on foot, there's an incline to get up to the chateau but it shouldn't be a problem if you are in reasonably good shape.
If you are coming via train from Prague, my guidebook says it's an hour train ride with a 2 km walk from the train station with infrequent bus service.