In this letter, the joint synchronization and localization problem in asynchronous networks using time-of-arrival measurements is addressed. A novel two-step method is proposed. In Step 1, we estimate the clock skew by a linear weighted least squares estimator. In Step 2, we obtain a second-order cone program (SOCP) by applying second-order cone relaxation technique to jointly estimate the source node location and clock offset. The relaxed SOCP problem is further tightened by adding a regularization term. Moreover, a simple procedure of selecting the regularization factor is proposed. Simulation results show the superior performance of the proposed method over the existing methods.