Lookup 'William Still, The Underground Railroad'

He was an abolitionist and a conductor of the Underground Railroad. He interviewed hundreds of runaway slaves, kept records and wrote biographies on them.

edit: also, I know there were tribes in florida that took in runaway slaves. If they converted religions they were compensated for with shelter, food, work, security, etc.

Though you are likely referring to the African Slave Trade, and African slaves' attempts to return to their homeland, when we talk about slavery in early English colonies in North America we should not forget to focus on the Indian slave trade.

The Indian slave trade permeated life in the early U.S. colonies. Early contact along the Atlantic Coast was often initiated by traders or fisherman who, in an attempt to make a quick profit, would kidnap Amerindians living along the coast to sell as curiosities/slaves in Europe or the Caribbean. In the south, the Indian slave trade was the most important factor influencing the development of the Carolinas from 1650-1715. More Indians were exported out of Charles Town than Africans were imported during this period (Gallay 2009). Slavery became a feature of total warfare with Indian nations, as seen in Massachusetts at the end of King Phillip's War, when the defeated remnants of the Wampanoag Confederacy were sold into slavery in Bermuda.

Perhaps one of the most famous Native Americans, Squanto (or Tisquantum), was originally abducted with five other members of his Patuxet village in 1605. He managed to return to New England in 1614, only to be abducted again shortly after his return. His captor, Thomas Hunt, then sold him to clergymen in Spain. From Spain Tisquantum made his way to London, where he lived for a few years before boarding a ship to Newfoundland in 1617. He arrived in Newfoundland, but couldn't find transport down to Massachusetts, and returned to England. Finally, in 1619 he journeyed with John Smith back to his Patuxet village, finding the area depopulated from slaving raids and disease. A year later the Mayflower made landfall in Plymouth and Tisquantum began his role as translator/guide/ambassador between the Plymouth colonists and the Wampanoag leader Massasoit, aided by the English language skills he gained during his captivity.