Most sink manufacturers state the required cabinet size on the box, if not then a reasonably competent store employee should be able to provide it. A 36" cabinet size will fit most common sinks, and as majak said it is really up to you to decide what your requirements are.
I personally prefer a standard double bowl setup, but if you have a dishwasher you may want to consider one oversize bowl with a smaller rinse sink (similar to a sink and a half).
Also keep in mind where the drains are and what your plumbing setup is. If you are trying to re-use your existing plumbing then you will want to make sure the drains are in the same spot as your previous sink. If you are doing a fresh install, consider getting a sink with the drains towards the rear of the bowl as opposed to in the middle; This means that your plumbing will be closer to the wall and leaves you with more storage space in the cabinet below the sink.