RustyC

Am sure there are a lot of resources for looking things up, but from personal experience I'd suggest staying as close to the Bukit Bintang intersection as possible (Jln. Sultan Ismail and Jln. Bukit Bintang). The Menara and Petronas Towers/Suria KLCC are musts, the national museum is worth a look and the Batu Caves are likely worth it (I saw during Thaipusam, when you really should go see it). Nightlife around Bukit Bintang is about as lively as it gets, there's Jln. Alor (the food street) and, in Chinatown, Jln. Petaling (rivals Patpong for the fake watches, plus other stuff). Daytrips include Genting Highlands and Melaka, or maybe one of those firefly trips (I did mine out of Cherating). They can also give tons of suggestions at the tourism office.