The main ones for extensive original language research are Accordance, BibleWorks, and Logos. If you want to get a taste of what the program is like before making a financial commitment, there are free trial versions you can download.
If you want to see how the full version works, Accordance offers a 30-day refund option for two packages. (a Starter for $60 and an Original Languages for $100)
Though not as oriented toward original language work, two other programs are worth considering.
The Word is one of the first I recommend to people not planning to invest in one of the programs above. This is a rather full featured program, and it’s free. Includes Greek / Hebrew. You can always buy some modules, e.g., NRSV, to expand its versatility. Only runs on Windows or under Mac emulation.