Seth Rockman, professor of history at Brown University, recently posted on the H-Net list devoted to the study of slavery about Brown's recent report on its "historical relationship to slavery and the transatlantic slave trade." The Brown family that helped endow that college soon after its founding included both slave traders and Abolitionists. After the Civil War, the institution naturally emphasized the latter connections, but it's now used its resources to explore how slavery and slave imports helped support its early years.
Prof. Rockman wrote:
For one thing, you can download the report [PDF, 6 MB], which contains an excellent narrative of the eighteenth-century Atlantic economy, the history of reparations, and the connection between slavery and how race is lived in America today.There's also a classroom curriculum. (Postings at Boston 1775 addressing slavery in eastern Massachusetts include items about a legless escapee, civil rights lobbying in 1773, and how activist judges ended slavery after the war.)
Also at this site, you'll find some amazing classroom resources for teaching the eighteenth-century slave trade. Some stunning documents from the Brown Family Business Papers (housed at the John Carter Brown Library) have been digitalized and transcribed.
Most relevant are those pertaining to the 1764-65 slave-trading voyage of the brig Sally. The entire logbook is available, making it possible to watch Capt. Esak Hopkins negotiate the price of every single man, woman, and child he purchased along the West African coast. The records also document a shipboard rebellion during the Middle Passage. You'll also find all the papers pertaining to the outfitting of the vessel, the hiring of the crew, the sailing instructions from the Browns, letters from Caribbean factors, and so forth. The scans are incredibly clear.