If you are preparing for the JLPT, you can view sample questions online:

Japanese-Language Proficiency Test Official Practice Workbook

For all levels, the official JLPT practice workbook contains almost the same number of questions as an actual test, with questions selected from among those used in 2010 and 2011 tests. This is the first official practice workbook for the JLPT since the 2010 revision.

Bonjinsha Workbooks

The workbooks are sold by Bonjinsha. See here for more details.