Second Chance takes in orphaned, injured, and sick Maryland native wild animals. They do not deal with domestic and non-native species. They also do not adopt out any of their charges to the general public. If you find a wild animal in need of assistance contact them.
Founded in 1992, the Phoenix Wildlife Center is a 501(c)3 tax exempt, non-profit organization dedicated to the rehabilitation and return to the wild of native birds, mammals, and reptiles and to the education of the public on wildlife issues.
If you are looking for a companion who is hard on the outside but lovable on the inside why not consider a turtle or tortoises? There are always animals up for adoption at MATTS. They also take in a limited number of animals. Check out these armored survivors.
If you are interested in a cat, there are many feline shelters out there. One of which is Rude Ranch, a non-profit no kill shelter dedicated to saving abandoned, neglected, and abused animals.
Of course there is also Petfinder.com for a more complete list of shelters from across the nation. They provide a list of available animals cataloged by type.