These are the ones I have stayed at. I am budget conscious. Ranked in order, with my first choice first and last choice last:
Crown Point Beach Hotel in Tobago:
In store bay, shared beach access with Johnston apartments. Store bay beach is a 30 second walk from your hotel room. Pigeon Point is about a 10 minute walk. 3 minute walk from the airport. Numerous good restaurants nearby. Comfortable rooms and friendly staff. Only disadvantage is a fairly high noise level at with various night clubs, airplanes etc.
Sandy Point Beach club:
They have their own beach, but when I was there, the water was way too rough to think about going in. Store Bay beach is about a 5 minute walk. Pigeon point is 15. Airport would be a 5 minute walk. Our room was a bit too cosy, but they have a wide selection of rooms. Nice big pools (yes, more than one). A bit of a walk still >10 minutes to get to restaurants.
Blue Waters Inn:
Located in Castara, you either need to rent a car from the airport, or take a taxi. I've heard roomers of an airport shuttle but cannot confirm. GREAT diving, snorkeling, bird watching, hiking, etc. Speyside is a little remote, great for relaxing and enjoying nature but shopping and dining choices can be limited. Price is a little high too.
Caters to younger crowd. They feautre the best kitchenettes of any hotel in Tobago I have stayed at. A pool is shared with the Crown Point Hotel. Store Bay Beach is a staircase away. Private beach access means you can bypass the pushy glass bottom boat salesmen.
I've stayed here numerous times. They boast a great value. The friendliest hotel staff I ever encountered. Period. Not beach front, but Store Bay is >5 minutes walk. A pool is shared with the hotel next door, I can't remember their name. Rooms are comfortable, with different options available. Plenty of dining options close by. Airport is a 2 minute walk. A goat farm behind the hotel makes it feel more remote than it is. The road outside of the hotel is home to 2 bars, popular with the locals. If you are unfamiliar with locals, they can be seem very boisterous and aren't shy about anything. Being a lady, you will be the victim of a few cat calls. Give them a smile, keep walking and all will be well.
Located in Castara. Nice beach. Nice people. A long drive from the airport. Rooms are a little cozy but nice. Its distance from the southern part of the island means it is great for relaxing, but like Blue Waters, dining and shopping options are limited. The beach is a 30 second walk from the hotel. No super markets are present in Castara, so either plan ahead, eat out or make do with a limited selection from small local stores. A car rental or taxi will be necessary to get to and from hotel.
Located in Buccoo, a "rustic" little place. Our room was in need of a make over. The Miller's are very friendly and accommodating. The locals that we encountered all seem more layed back and friendly than most other places. Sunday school is popular and worth the while. It has been a while since we stayed there though, and I have heard than crime in Buccoo is on the rise. Something you should research before you book.
A 3 hour drive from Port Of Spain, as with almost anywhere in Trinidad, a car or taxi will be necessary. During Turtle season (March through August) the village of Grand Riviere is very busy, understandably. The turtles are breathtaking. For a small village, there are surprisingly numerous dining options. The staff is friendly and accommodating. If you are a night owl, beware the bar closes after supper, around 9:30. Plan accordingly. The hotel provides beach chairs. Swimming in the ocean can be treacherous if you're not a turtle. But the river creates quite a large pond on the inland side of the beach that is really great for swimming. I have never stayed at the hotel next door, but it looks nice too.
Very quiet and beautiful spot. Fred, the owner is a card and great for a nights entertainment (No TV's in the rooms mean you will appreciate the company). The rooms could use a little updating, but they were still quite suitable. Hotel rooms are located up a hill from the main building. Each building holds (I think) 8 rooms. Each building has a large veranda, great for spending time. The beach is a 400 ft walk through the hotel property. The water can be rough here too, but there is a pond on the inland side great for swimming.