Forgotten Ohio
This site has everything. I would have to say it's definitely my favorite Urban Exploration site I've found. I credit this guy to much of the reason I started my page.
Illicit Ohio
Very similar to the above site. It has many of the same buildings and such, but is a great site and worth the visit.
Abandoned Ohio A great Ohio site with very awesome pictures.
Midnight Society
Probably my 2nd favorite Urban Exploration site. This site has some really great stuff from New Jersey and areas around it. A lot of the houses they visit still have clothes and furniture left from residents who appeared to have left rather abruptly. Just check out the Purgatory House.
Grave Addiction
A great site serving Ohio and the Eastern Seaboard.
Danvers State Insane Asylum
An entire site dedicated to my favorite Mental Institution. There are some great pictures of this massive Kirkbride structure. Enjoy the pics because the hospital is getting razed to build condominiums.
Northampton State Hospital (Old Main)
A great site dedicated to my second favorite Mental Hospital. This site is really well done. It has a virtual 3d tour of the whole place. It is setup to gain awareness of the Kirkbride to held preserve it. It truly noble cause.
Kirkbride Buildings
A wonderful site that lists many Kirkbride structures . It gives a great history about the architectural design if you are into that. It also some some other pictures of Danvers and Old Main.
A great Canadian site that has a little bit of everything. I think the best part of it is the ethics section.