As a close friend of Abraham Lincoln, it was Fell who urged him to challenge his opponent, Stephen A. Douglas, to their famous series of debates.

In 1831 Fell moved to Illinois, opening Bloomington's first law offices and beginning his career in real estate.

Fell invested in lands in Bloomington, Chicago, Milwaukee, Danville, and other places in central and eastern Illinois.

[6] He sold lots in Decatur, Lexington, Clinton, El Paso, Joliet, and LeRoy and in 1855 he purchased timber land and began operation a sawmill near Ullin in southern Illinois.

Fell was an enthusiastic arborist who developed an extensive park around his home, and was known for planting trees in his real estate holdings.

In the summer of 1869 Fell traveled to northwestern Iowa and selected a tract of about forty sections, more than 25,000 acres (100 km2) of land.