If you want to record your song, you’re going to need some decent software. But before purchasing your software, do some research and make an informed decision. Don't go buy the flashiest, most expensive stuff out there. Odds are, you won't use 80% of what those programs have to offer anyway.
First, figure out what type of recording you want to do. Do you want to record guitar tracks only? Will you want to record your whole band? What type of sound quality do you want? Demo or professional? Do you want to record live instruments along with with programmed instruments?
If you play guitar, getting a quality guitar sound is the first and most challenging step. I highly recommend getting Line 6's GuitarPort. This software provides plenty of guitar tones and is really easy to setup on your computer. Achieving a killer guitar sound doesn't get any more affordable or convenient than Guitarport.
If you are a guitarist without a band, but you want to compose songs with all types of instruments, you will need software with programmed instrument capabilities. Steinberg Cubase is an excellent option. You can compose and sequence instruments such as drums, keyboards, and bass, using Cubase's virtual instruments. And you can still record your guitar live as well. So with this software, you have everything you need to compose and record a full song with plenty of realistic sounding instruments.
Usually, the most difficult virtual instrument to get realistic sounds with are drums. If you want to get drum samples that are as realistic sounding as it can get, look into getting a Toontrack sampling kit. The included samples will blow your mind with their authentic sound and dynamics.
If you are new to the world of recording software, just take it slow and do some research to find what is best for you. Stick to the basics and buy only what you need. It will save you a lot of headaches and will make your recording process more enjoyable.
For other cool software options, click here.