Dear Allan,
I recently had to find the home of one of my ancestors, in Ilkeston, and went to the library there.
The library has its own local history section and has many resources which might help you track down Hill Top Farm:
Maps (various decades and areas)
Local newspapers on microfilm
Rates books
Local books on the history of Ilkeston and surrounding areas - Heanor and Codnor should come under these
etc
I have always found the staff very helpful, not only when I visit personally, but also in responding to phone calls and letters.
They usually only charge for photcopying costs.
The telephone number is:
01159 301104
Hope this helps.
Kind regards,
Paulene

P.S. I'll be interested to know if you track it down.
Just thought, I'm sure Heanor has a local history society - should be on the web. There's always a possiblity that someone with local knowledge might have come across it. Good luck!