  A commutative Rota-Baxter algebra can be regarded as a commutative algebra
that carries an abstraction of the integral operator. With the motivation of
generalizing the study of algebraic geometry to Rota-Baxter algebra, we extend
the central concept of localization for commutative algebras to commutative
Rota-Baxter algebras. The existence of such a localization is proved and, under
mild conditions, its explicit constructions are obtained. The existence of
tensor products of commutative Rota-Baxter algebras is also proved and the
compatibility of localization and tensor product of Rota-Baxter algebras is
established. We further study Rota-Baxter coverings and show that they form a
Gr\"othendieck topology.
