I agree with Chuck.
A single library bundle, or perhaps 10, won't have much impact. You'll need to bulk up your library, and add to it over time. When your library grows, you'll see it take off.
A story from my own experience: I began selling individual downloads about 6 years ago. I had 2,500 sounds. I placed them on a handful of websites. They did ...
500 to 1000 downloads of a single sound library? No, you're probably not going to get that. 50 to 100 downloads maybe, and it would probably take you a year to get close to that number. 10 to 20 downloads of a library is realistic. I'm not trying to be negative, just being honest. The market is just not that big.
Now, if you're offering thousands of ...
Apart from strictly "audio production work":
• Selling sound effects and sound effects or sample libraries
• Preset design for musical instrument or audio effects plug-in developers
• Marketing for musical instrument and audio gear manufacturers
• Renting recording gear and studio facilities
• Acoustical consultation and studio design/building (but you need ...
Field recording is the most crowded area of SFX libraries. For a passive income you may need to find more specific areas.
For contract works, without a portfolio, the only way is to go for your close circle and try to join projects of someone you know in person.