I have been solving Thermodynamics problems for a few years and I have found a few websites and tools that I find pretty helpful.

Here are the best ones.

• NIST Webbook
  • This is a great site paid for by the US taxpayer. So, it is free to you !
  • Reliable values of properties of almost anything
  • Internationall accepted values of thermodynamic properties of most of the fluids that show up in LearnThermo.com or in any Thermodynamics textbook problem.
• Answers.Yahoo.com
  • You post your question with a time limit for replies and other users post answers to your question.
  • You decide which is the best answer
  • I answer thermodynamics questions on this site on a regular basis.
    My screen name is Dr. B from LearnThermo.com