This is a question I get a lot from both mentoring students and people who read my blog. As such, I thought I'd take the time to answer it.
I'd strongly avoid software products that you install on your computer. The data is often "mined" and / or sent to 3rd parties. In terms of availability, go to the source and use a registry (or a registrar you trust) to do the lookups.
It'd be wrong to suggest that only software installed on a PC is capable of falling victim to this.
Your post gives the impression that this can only happen when software is installed on a computer which is simply not true. In fact, one could argue (I would) that if the aim is to mine data, a web based platform would be far better suited to this!