I'm pretty sure you can use ion chromatography to get sulfate, sulfite, and thiosulfate. Contact your IC instrument provider for the best column for your needs. If you don't have an IC you can do sulfite by iodometric titration and sulfate by gravimetric or turbidimetric methods. I'm not sure how you would do thiosulfate by wet chemistry means. Sulfide can be done via a few different methods. Depending on suspected interferences and desired detection limit you will probably be best served by the iodometric titration, ion selective electrode, or methylene blue methods. Those should be your main categories of sulfur species. I guess you could get a total sulfur analyzer and see if there is anything else present that is not accounted for in the aforementioned categories.