In 1995, I purchased a PC so that I could use the BibleWorks program. It was a great program then, but it has so much more capability now than it had 11 years ago [partly due to the way computers have developed, but also due ot the painstaking work of Michael Bushell and his team]. The program is not inexpensive, but it is well worth the asking price, due to the excellent aftersales service you get, and the way the program is continually updated and upgraded.
The best free program is e-sword, which has lots of bible versions not available in BibleWorks. It is a great program, especially when you consider it is provided free of charge. It has nothing like the capabilities of BibleWorks, but the price is right! The developer offers the program free of charge, and so far there have been over 3 million downloads of the program. About 1% of these people pay a suggested $15 USD, for which the developer sends them a CD ROM which contains most features of the program. You can download it free of charge, but having a CD can be convenient. I've used the 2 I've purchased so far to give away to spread the word about this great program.