A couple of points :
1. You can try mailing/contacting the support department of the creators of the ACT software. If enough people mention that they would like to have native Linux support, maybe things will change... someday.
2. Wine is an freely available reverse-engineered implementation of the Windows API set. This means that you can _always try_ to get a Windows program running under Linux, I myself have had some success in the past with Wine for running a Windows program (Forte Agent), luckily I found a very nice native Linux replacement (PAN) so I no longer need Wine and Forte.
3. Another possibility is a tool called VMWare. This is a commercial tool. It creates virtual machine on your computer, in which you can load another operating system.
4. Yet another possibility is a program called CrossOver, which is a commercially developed version of Wine. See the following URL : "http://www.codeweavers.com/products/crossover/"