Lexx said:
Why do you lie. You will never find a group of mantises in the game after just 5 minutes of playing.
5 minutes may or may not be a ballpark figure, but I know I've run into manti more than once on the V13-Shady Sands-V15 run. It's not implausible.
Harlsberg, I'd mirror woo's sentiments, though. You don't normally have that kind of bad luck right off, and Shady Sands is literally the first town in the game you reach on a typical playthrough. F1 is really a masterfully-told story, and it's worth seeing these things for yourself. Turn down the combat difficulty if you have to and remember that you always have the option of running for an exit grid.
As Lexx says, the wikis do have most of the pertinent information that we could give you (and more, considering that there's a lot more available on its history than they give you in the games). Shady Sands was a small, adobe-walled agricultural village whose inhabitants (originally, dwellers from Vault 15) had a thing for simple, virtuous living, hard work, and deference to authority. Through perseverance, good leadership, and a deus ex machina in a blue-and-yellow jumpsuit, they somehow grew to become a modern(ish) city-state in the 80 years that passed between Fallout 1 and 2, and traded the simplicity and some of the virtue for a shrewd expansionist drive somewhere along the way. About 40 years before New Vegas, the last of the Shady Sands-era leaders died and a lot more bureaucracy and corruption started to creep into the mechanism of authority than had been present previously.
I (and the wiki) can mostly just give you the facts, though. Playing is really the only way you'll get the "feel."