Music Notation Software William Wieland
The best prices may be through Music Stores rather than directly from the companies. If you buy seat licenses or lab packs you can save more money. Upgrades are about one third of the original price. Finale and Sibelius are currently the dominant music notation programs.
Finale Notepad FREE • Unable to copy and paste
• Limited to 8 staves
• But it's free!
Sibelius Scorch FREE • Can display and print Sibelius files
• Unable to create files
• Yes, unable to create files
Finale PrintMusic ca. $120 • The software I recommend to most musicians
• Performs most functions you expect of music notation software
• If you like it and want more features, you can upgrade to Finale for a reasonable price.
• A free trial is available
Sibelius First ca. $120 • If I knew Sibelius products better, this might be my top recommendation
• Performs most functions you expect of music notation software
• A free trial is available
Finale (academic
edition)  
ca. $350 • The music program I know best
• Prints music, words and graphics
• A free trial is available
Sibelius (academic
edition)  
ca. $300 • Many claim Sibelius is easier to learn than Finale.
• A free trial is available
SmartScore and PhotoScore scan music. Both are available in less expensive, “lite” versions. Note that Finale and Sibelius each have scanning capabilities, just not as good as these two stand-alone programs.
MuseScore FREE • Open source software like OpenOffice (free word processor) and GIMP (free graphics program)
• In my opinion, MuseScore is the best free music notation program.
• If you seldom use a program, I recommend open source software.
Noteflight FREE • Online music notation application
• Well suited for mobile devices like the iPad
• You can upgrade to Premium for $8/month or $50/year.
Notion ca. $150 • The top challenger to Finale and Sibelius.
• The price is right.
Many more music notation programs exist than I list here including those designed for guitars like Guitar Pro.