Lactic Acid peel, whatever concentration you want, its great for pigmentation and doesnt leave you with all the common side effects from most peels. Just one question, have you been exfoliating with anything, Retin-A? Manually? or scrubs for a few months? if you have then Lactic is for you, if you havent exfoliated consistently till now then use glycolic or TCA because that will lift all the years of dead skin cells you have built up.
According to Lexi Lactic Acid has: "a deeper method of action. In other words it does not PEEL the dermis, which causes downtime, but rather penetrates it and stimulates it." So the Lactic Acid basically stimulates your dermis which produces the formation of new collagen, giving your skin its health back (Retin-A does the same thing, it stimulates and helps your skin make collagen). Lactic Acid is sour milk so the added benefit of using it would be a lightening effect on your skin, and it also inhibits tyrosinase which is an enzyme responsible for making skin color.
These are the three places to buy Lactic Acid from:
Makeupartistschoice.com -> this place has Lactic Acid in various concentrations.
Beautyscientific.com -> this place has upto 50% concentration of it.
Amazon.com -> you will get the best price here and also the highest concentration I have seen which is 85% Lactic Acid for 20 something dollars, which is great.