I want a Realtek device, where can I get one?
These are current devices; the Alfa AWUS036H is a highly recommended device by both the KisMAC and the Aircrack-ng development teams. They offer 300 mW of transmit power out of the built-in RP-SMA connector (put on the stock 2 dBi antenna and you have 500 mW!), and have phenomenal receive sensitivity in spite of that power. The lower-powered version are the AWUS036EH (300 mW w/ antenna) or AWUS036E (50 mW w/ antenna). You can find them from eBay stores SimpleWiFi or Data Alliance (WARNING: Data Alliance are known for not honoring warranties), or Rokland. After you buy, try getting drivers from the vendor’s website (if you want to use the device to make network connections). Or if you just want to use it with Kismac, skip that. Just keep in mind that you can’t use any rtl8187 device with Kismac while the OS drivers are loaded.