Saint Dominic de Guzman (c.1170-1221) was the itinerant preacher of early 13th century southern France licensed by Innocent III for whom is named the Dominican order founded at Toulouse (formally,'The Order of Friar Preachers'); those same Dominicans who were generally university-trained theologians and preachers. It should then come as no surprise that some of the most dependable histories of the Dominican order have been written by university-trained modern Dominicans.

The standard history reference for researchers is M.H. Vicaire (OP) 's Histoire de Saint Dominique (Paris, 1957) translated into English by K Pond and published in the 1960's variously as Saint Dominic and His Times and The History of Saint Dominic (New York, London) . Vicaire has revised his work since first publication but it's only published in French (Paris, 2004).

As well we have William Hinnebusch (OP)'s 2 volume The History of the Dominican Order in (New York, 1966).

Of course one needs to take these apologetic works critically, for example, Hinnebush in his short summary available here opens with:

St. Dominic was a spirit-filled man raised up by God to answer the pressing need of the Church for a continuous body of trained preachers. Guided by the Holy Spirit he founded the first apostolic Order, combining the contemplative consecration and apostolic ministry of the twelve apostles and the primitive Church.

But still very valuable and referenced by most scholarship.

As well, Simon Tugwell (OP) published some valuable sources in translation including Early Dominicans: Selected Writings (New York, 1982) and Jordan of Saxony's On the Beginning of the Order of Preachers (Dublin, 1982).

There is a decent short biography by V. Koudelka, Dominic (London, 1997).

Most non-Dominican scholarship on medieval Dominicans in the last 20 years has come through projects on their role in preaching against heresy and in development of the medieval inquisition. If you are looking for recommendations on those let me know.