Hey Erion
First welcome to the forum....Now, about your question...There is various sequencers available. I would recommend Sonar Studio XL4, Reason, or
Cubase SE 3...Notice that just because it's Cubase or Sonar doesn't mean its expansive.
Every sequencer has a different and simple versions applied more to the needs of a beginner.
Here is a page where you can check out info (and their price) of practically every sequencer available on the market. They are sorted by brand
http://www.audiomidi.com/master.cfm?CID=105
Note that Reason isn’t there, cause reason isn’t a sequencer “by heart”. It’s a standalone virtual studio actually....Basically it has everything you need to start, and great quality and stability as well. Although I would recomend you to take a look on others optioms and see which one fits your needs better
Hope this helps
Cheers