I'm purging my life, and that includes selling a lot of things I own, included in that is my manga collection. D=
At the moment I'm only selling to UK postal addresses, and I'm using www.greenmetropolis.com (which is great.) you can post any book on there and every book costs £3.75 (Unless it's really heavy.)
I've got several titles, including Tokyo Babylon, DNAngel, Trigun, D.Gray-Man and many others.
Please check it out at https://www.greenmetropolis.com/member.asp?id=140750