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[2012 - I've been looking for Linux tax software, and found OpenTaxSolver! Everything else is going online, which is fine for most people... but last year I failed to file my 2010 taxes. I got an extension and paid, but for various reasons could not file. So I need to file old taxes, and you can't find that online. Fortunately, I bought downloadable software (H&R Block), and can finish that up. So it's good to purchase a downloadable for some cases. The problem is, downloadable softaware now seems to be a Windows-only product.]
TaxACT - basic prep software to do the short and long forms as well as what seems to be all the common small business forms. The free version does ALL the forms, including Schedule C. The paid version offers advice. Online or Windows only.
H&R Block at Home - basic to advanced. Some versions do Schedule C and other business forms. Comparable to TurboTax. This used to be called TaxCut. Available for Mac and Windows.
In the past four or five years, I've used all these apps. TaxAct is simple and plain (and cheap). TaxCut (H&R Block) is like TurboTax, but with less help. TurboTax has the most help and advice, but is also gives you the most "maze like" experience.
If you're new to tax prep, H&R Block is a good way to learn. If you already know tax prep and basically have the same return as last year, TaxACT is probably easier than the other two, because you can deal with your taxes by filling forms rather than having Q&A interations with "wizards."
Also, if you have a micro business, rent property out, or lots of 1099 income, something to try is to purchase the more expensive software one year, and use all the wizards, and really learn the tax forms. Then, the next year, purchase TaxAct, and use your past return as a guide to preparing your next return. This will work if your income sources are similar year after year, and the business tax laws don't change significantly (and you regularly read a business magazine to keep on top of what deductions are available).
Also, some states have free online tax filing. California, for example, has two different online forms. One's called Ready Return, and is almost one-step filing. The other is called CalFile and is more like a traditional filing program, with multiple income sources, deductions, and other tax features.