I have friends who live on the island of Tortola so I have been there many times and I love it! I can't help you with accomodations because I always stayed with friends.
As for what there is to do, there are some must visit beaches! If you have a vehicle I highly recommend Smugglers Cove. It is a very secluded beach with very few, if any, people on it especially on a week day. Brewers Bay is excellent for snorkeling. Cane Garden Bay is probably the most commercial beach with a nice selection of beach bars and restaurants. This is a great beach to visit in the evening for live music.
If you will be there during the full moon you have to experience the full moom party at Bomba Shack! You will never forget this fun party!!!
The botanical gardens are very nice and worth a visit. There is also a panoramic restaurant at the top of the island although I don't recall the name of it.
My favorite restaurant/bar is Spaghetti Junction (restaurant) with the Bat Cave (bar) owned by John and April who are originally from Canada. If you do go there please tell them that their friend, Tamara, says hello.
You can also visit Marina Cay, which is now called Cuervo Nation (I think). It is a nice little island right off the tip of Tortola.
You must visit Pussers Bar and drink one of the famous Pain Killers. There are three different potencies so be careful if you order a #3! You won't be feeling any pain after a couple of these!
Prospect Reef seems to be a nice hotel but I haven't been in any of the rooms.
You should definitely take a ferry over to Virgin Gorda to visit The Baths. Gorgeous!
Feel free to ask any other questions!
Tortola is a fantastic island!
