IMPORTANT!
If you want to retrieve a deleted file, first of all, STOP using the hard disk where the deleted file is/was, anything you do with this disk will likely write over the space where the deleted file is, the bigger the file is the bigger the likelihood of this happening, since we are talking about a virtual machine, it's a several GBs binary file, all it probably takes is overwriting just some bytes of this space to completely kill any possible recovery, so the likelihood that this already happened is very high (for instance when you installed the recovery program, if it was on the same computer).
Since this file probably is in the system hard disk on your computer, you should do this from another computer, by either connecting the drive to another computer or using your mac in 'target mode' (google it).
Finally, .pvm is not a file it's a package, it's like a folder where all the files related to the VM are located, the file you should be looking for, the most important one is the virtual disk file, the extension is .hdd (which is also a package), and inside it the actual virtual disk are some .hds files.
If and only If the VM is really important, STOP using the computer where it is/was and consult a specialized data recovery technician in your area, also create a ticket with Parallels support (I'll explain why).
Let me give you the truth right away, it's very unlikely you will recover your VM, because it's a really big binary file, secondly the format the file is in is not publicly documented, hence you'll need Parallels assistance, and finally data recovery can be expensive. In the future, backup backup backup.
I'm sorry.
Last edited: Nov 10, 2012