I got a Lexicon Alpha recording interface for Christmas. Sort of a replacement to my other busted interface. I can plug an instrument cable in and everything works smooth, but when I try to get a microphone going, nothing happens. I'm using Cubase 5 LE and have an MXL 990 microphone. Any assistance would be greatly appreciated.
The most obvious solution I can think of is that you're probably not running phantom power for the condenser mic.
^ I'd agree with that. Upon a quick google search, it looks like the Alpha does not have phantom power built in, so TS will need to purchase an external phantom power supply.

Could I get some more talent in the monitors, please?

I know it sounds crazy, but try to learn to inhale your voice. www.thebelcantotechnique.com

Chris is the king of relating music things to other objects in real life.