If I asked people what they wanted, they would have said 'Faster Horses'. -Henry Ford
Make sure that you focus on goals.
Don't ask what your users want or need in terms of functionality or form. Find out what they need (or want) to achieve .. that way the parameters you use to define and solve the problem will be much clearer and focused.
Questions to ask your users might run along the lines of;
- what they need to achieve.
- how they currently achieve 'x'
- moving on to find out what makes current methods difficult.
Don't carry out user research for solutions - research problems