The Petronas Towers are part of the KLCC (Kuala Lumpur Convention Center (Centre)), and it seems like everyone calls it that.

The base of the towers has a huge mall with a food court on one of the upper floors and restaurants on two of the upper floors. You can get tickets to the skybridge connecting the towers at the 42nd floor, but be sure to get there around 8:30 (or earlier?) in the morning to get tickets.

To get there, you can take a taxi. From within the “Golden Triangle” (which I hadn’t heard named before), the business district downtown, it should cost you 5 ringgit (~$1.33) or less to get there. I successfully bargined cab drivers to 5 starting from 10. Some cabbies do not bargin but use a meter, which may come to 2.50 or 3 depending on traffic and whatnot.