Just as a note, the starting cities are perhaps not all that different in alignment, just in atmosphere and surface activities and the...leanings of the majority and those in power. I would be hard-pressed to label Hempstead LG as much as I would Vehl as purely NE/CN, hehe. More likely TN for both, or perhaps NG for Hempstead. Civilized society or not, there is a boisterous, rowdy, furniture breaking CN Shadonite tavern that is the most frequented tavern near the docks, for example

As well, Deliarites make up a large part of the city's economy, and many of them have more free-spirited CG ideals than say, a monarchy would. So it balances out somewhere with with the inherent lawfulness of enforcing authority, just like despite the CN-NE feel of Vehl, there is a temple to a LN god that is the ...'authority' in the area.
It is possible to start off in Hempstead even if one is evil, as long as one were not blatantly so (dressing in eeeevil black spiky robes with eeeevil creatures as familiars and preaching about the destruction of the world, praising eeevil gods and the usual stereotypical eeevil behavior *waves hands dramatically*). It would just need to be a more gentlemanly evil so as to slip under the radar. Likewise, darker good people that are estranged from society (social outcasts, solitary brooding yet CG rangers etc) may well find themselves in Fort Vehl as well, because of the place's "mind your own business" attitude about most things...
There are a few things that everyone should have some basic knowledge of IC, but not all that many because as minerva stated, many commoners do not venture out and get education about other places and events in the world. Some examples of universal knowledge would be the war with Bloodstone, the sudden darkness of the skies that lasted almost 20 years, and the later cleansing of the skies a few years ago... but as she also stated, if you toss together something to submit or have a general idea on starting points, we can help you hash it out in your submission. Welcome to Layo!