What you want to find out will determine the method and tool you choose.

Attitudinal user research methods reveal user attitudes and opinions, how they feel about a product or service. Examples are:

• Focus groups
• User interviews
• Graffiti Walls
• Diary studies
• Surveys
• Love/break up letters
• Photo studies

Behavioural user research methods tell us how users actually behave, how they interact with and use the service. Examples are:

• Customer journey mapping
• Usability testing
• Contextual inquiry
• Observation/behaviour mapping
• Cognitive mapping
• Touchstone tours

For example, if you're looking for feedback on library space, observation/behaviour mapping would be an ideal starting point as it will give you information on how people are actually using the space. If you want feedback on a workshop you've run, a quick exit interview might be all you need.