I can route you the download links, mmansoorf
As mentioned above, you can only download the latest QuickBooks Desktop trial version on your computer. Feel free to browse the links below to get free trial versions. This won't require a product and license key.
After that, open the downloaded file and then install the program. Also, if you're about to convert the your client's company file to QBO, I'd recommend reading this article to be guided in performing the process: Move your QuickBooks Desktop file to QuickBooks Online.
For more tips and resources while working in QBDT, you can browse a topic from our Help Article page.
If you have other questions, you can always visit us back here and we'll be happy to answer them.