I am a lifetime member of LibraryThing. I enjoy using it very much. Now that I have come back to the states I do not have very many books. I left my library with my son, Chris Gardner, in Arequipa, Peru.
However I try to enter each new book that I get into LibraryThing. It is just a system to keep up with my books and all the information about them. I now purchase many books via the Kindle but I also add them.
I think you might enjoy LibraryThing and so there you go, go check it out. Here is my library for the moment.