There are a few ways you can do this.
1. In Excel you can connect to a database and have the query come back to a worksheet.
2. If it is a 1 time thing, you can use the data import/export wizard. Right click on the database you are pulling information from and the Import/Export data option comes up. You select your database as the source, tell it you want to use a query to specify the results, and then tell it to go to excel as the output.
3. If it is a repeating task, setup a report in reporting services. Your users would be able to export into a csv file from the report.