2001 Chevrolet Impala 3.4L Engine Modifications?

Ok so I recently got a 2001 impala 3.4 and I need to add some horses to it. Are there any good/cheap super or turbo chargers that would run at a safe psi but still give me good boost? I heard that these vehicles can only handle 6-8 psi of boost, which is fine with me. Any other suggestions for engine modifications? Oh and please include sites. Thanks :D