Just curious about this...what is the reason for wanting to determine if a number is land or mobile?
For households, a home number typically allows you to reach both spouses while a cell phone is usually one or the other.
Organizations with outbound calling also like to know what kind of number they are calling, though in my consortium no organizations currently do any telemarketing/telefundraising.
The site I currently use for manual lookups is area-codes.com, ex: https://www.area-codes.com/exchange/exchange.asp?npa=805&nxx=899
-- Mike