Honestly, you can find beachfront villas on just about every island but the difficulty will be finding one that is small (most beachfront home tend to be on the large size to accomodate families and groups). That doesn't mean you can't find smaller units you just have to look around more. You also mentioned that you are considering a "tropical weekend getaway". At that time of year, you may have difficulty finding a villa of cottage that will rent for just the weekend. January is "high season" in the Caribbean and most villas and cottages have minimum stay requirements (usually at least a week). If you can't find a small cottage you might consider staying at a smaller beachfront resort, boutique hotel or condo (you'll get a feeling of intimacy without the crowds of a major resort or hotel). Also, many of the islands are difficult to get to so if you are going only for a weekend you might want to limit your search to those islands you can get to directly from your departure city. If you tell us where you are traveling from it will be easier to make recommendations.

Since you've never been to the Caribbean you might be interested to know that no two islands are alike and each has it's own unique appeal. You might first want to determine what type of experience you want. For instance, do you want an island with lots of shopping and an active night life or are you dreaming about quiet seclusion? Do you want access to casinos? Are you interested in an island with spectacular beaches but that is rather flat and featureless or would you prefer the lushness of tropical rain forests, volcanic mountains and waterfalls? Do you want an island with a European feel or are you looking for "old world caribbean"? Does the color of the sand matter? Many of the lush volcanic based islands have darker sand while the flatter coral based islands have whiter sand. Do you crave upscale dining or or prefer the comfort of fast food places? Are you the type of people who are content to sit on the beach all day long or would you rather go out and explore the countryside? Are you into diving? Are watersports important to you? No one island is going to "have it all". Try to narrow your search to the two or three islands that most appeal to you. Then you can look to find the type of accomodations that will best suit your needs.