Excel Add-Ins for Psychrometric Chart and Steam Properties 1

[teaspirit]

Hi All,
Can anyone recommend an Excel Add-In for obtaining psychrometric data as well as steam conditions? I've found some freeware and $100+ programs, but I'm curious to know how to get the most bang for my buck. Looking to spend $50 at the most. Thank you.

 

[TD2K]

Steam-Tab is free but it only gives you steam and water properties. Just google it and you'll find it.