Using a Trigger Finger with software is the way to go.To make good quality beats you should have a good computer with atleast 1gb of ram, and its good to have 2 hard drives (1 for music and one for software).You also need a good pair of monitors (don't get cheap ones). If you dont have money for them get a pair of headphones (Sony MDR-7506)which are $100.
Getting a good quality interface will help alot too.The EMU 1212M is good and only $200 . this is an article from a site explaining what an audio interface is
"Audio Interfaces
Over the past few years, musicians have been opting for audio interfaces over standard soundcards. These may be either PCI or Firewire. The AI typically has a breakout box that sits outside the computer and a cable that is connected to either a PCI card in the computer or a USB or Firewire cable. On this breakout box are a number of connectors for cables that go to your instruments, mics, mixer or monitoring system. The conventional soundcard, on the other hand, just sits in the computer in a PCI slot, the cables hang off the back of the card.
The audio interface type of system is often preferred because the cables stay away from the fierce electrical fields that surround the modern computer. That argument does not hold a lot of water, and it doesn't bother the guys running hi-end RME and Lynx cards. But this argument does...
Audio interfaces also sometimes allow for balanced audio connectors instead of the unbalanced 1/8" stereo jacks one sees on most cards. If you want the cleanest possible recordings, then go with an audio interface that has balanced connectors."