I want to offset my carbon footprint, but I'm not sure what company (if any) is really making effective changes. Bill Gates says he pays $400/ton of CO2 he offsets - but the companies I've seen imply I can make my entire footprint of around 30 tons per year disappear for $150. That doesn't really line up. And with this being a product that isn't tangible I worry about the likelihood of being taken advantage of. How would I ever know if they're using my money in bad faith?

I've held off on buying any offsets so far because of these concerns.

It's honestly hard to separate out companies who are genuinely making a decent effort to not be completely terrible versus those that are just green- or ethical-washing their practices as a marketing tactic. Furthermore, I realize that reducing consumption itself is the most sustainable choice one can make, so I'm asking this more as a "when I do need to buy something, what's a good place to turn to?"

Feel free to give recommendations for any areas, but in particular I'd love to hear about recommendations in the areas of clothes, linens/bedding, and coffee beans, as those are things that I'm currently on the market for. Also, if there are any good resources that aggregate reliable information about sustainable companies, let me know too.