It would help for making recomendations for stores if you'd include a country and state or province in your User information or at least tell us in one of your posts where you live.

Zefal and Park are the two big bicycle tool makers. Typically you buy their specialty tools through bike shops or places such as MEC or REI or similar full service outdoor sports stores depending on which country you live in. Or you can buy these tools from the online big bicycle suppliers such as Cambria or Jenson's.