Question
QUESTION: On 07/27/2007 I was awaken, by a loud screech, almost like a vulture sound, my puppy started growling, so I jumped up to discover her pawing at something on the porch. I grabbed my glasses and it looked like a lime green skinny lemon shaped bug probably about and inch in height making this loud high pitched bird sound (almost like it was getting ready to attack. I didn't know what to do so I squished it. I went out this morning to look at it but it was gone. I'm sure Chloe ate it?? What kind of bug do you think that was?

ANSWER: These are cicadas.
A cicada is an insect of the order Hemiptera, suborder Auchenorrhyncha, in the superfamily Cicadoidea, with large eyes wide apart on the head and usually transparent, well-veined wings. There are approximately 2,500 species of cicada around the globe, and many remain unclassified. Cicadas live in temperate to tropical climates where they are one of the most widely recognized of all insects, mainly due to their large size and remarkable (and often inescapable) acoustic talents. Cicadas are sometimes called "locusts", although they are unrelated to true locusts.
Cicadas do not bite or sting, are benign to humans, and are not considered a pest. Male cicadas have loud noisemakers called "tymbals" on the sides of the abdominal base. Their "singing" is not stridulation as in many other familiar sound-producing insects like crickets (where two structures are rubbed against one another): the tymbals are regions of the exoskeleton that are modified to form a complex membrane with thin, membranous portions and thickened "ribs". They rapidly vibrate these membranes with strong muscles, and enlarged chambers derived from the tracheae make their body serve as a resonance chamber, greatly amplifying the sound. Some cicadas produce sounds louder than 106 dB (SPL), among the loudest of all insect-produced sounds. They modulate their noise by wiggling their abdomens toward and away from the tree that they are on.
Here is a web link to more information on cicadas.

http://www.ivyhall.district96.k12.il.us/4th/KKhp/1insects/cicada.html

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QUESTION: so is Oklahoma a normal location for this type of bug?

Answer
Yes cicads are common in Oklahoma. Oklahoma is home to at least 12 species of cicadas. Each year they emerge from their underground hideouts, shed their skins, fly to the treetops, mate and then die. Differ璭nt species have different life cycles. Most cicadas live under璯round for two to eight years, but Oklahoma is also home to a cicada that biologists call Brood IV, a species that has an impressive 17-year life cycle. Many researchers believe this gap between emergences keeps predators from growing accus璽omed to the plentiful food source that cicadas offer. North America is home to approxi璵ately 100 species of the 1,500 known in the world.