Summary: This work is concerned with pricing American fixed lookback put options. The underlying asset is modeled as a switching diffusion process, where the switching is represented by a continuous-time Markov chain. The switching diffusion delineates stochastic volatility effectively. Nevertheless, this formulation together with the lookback style put option makes it virtually impossible to find closed-form solutions. As a viable alternative, a stochastic approximation algorithm is suggested. The convergence and rates of convergence of the algorithm are established.