Olivia Remie Constable, Trade and Traders in Muslim Spain

Michelle Hamilton, Representing Others in Medieval Iberian Literature (this is a great book, but probably not affordable unless you have access to a university library)

Thomas Glick, Islamic and Christian Spain in the Early Middle Ages

Kathryn Miller, Guardians of Islam - Muslim populations under Christian rule after the Reconquista, from Islamic sources

David Nirenberg, Communities of Violence - looks at case studies in Spain and France

Brian Catlos, The Victors and the Vanquished: Christians and Muslims of Catalonia and Aragon, 1050-1300

Stephen Haliczer, Between Exaltation and Infamy: Female Mystics in the Golden Age of Spain

ETA: Olivia Remie Constable, ed., Medieval Iberia: Readings from Christian, Muslim and Jewish Sources - a massive, wonderful collection of primary sources in translation

My favorites from this list would be Constable (both of them) and Miller.

Oh I have so many. I'll try to be coherent about this, bear with me.

A good concise general work on medieval Iberia is The Medieval Spains by Bernard F. Reilly. Another good one is a bunch of collected primary document excerpts called Medieval Iberia: Readings from Christian, Muslim, and Jewish Sources edited by Olivia Constable.

On Moorish rule:

Rise and Fall of the Party Kings and The Caliphate in the West by David Wasserstein are both good, but hard to find.

The Ornament of the World by María Rosa Menocal, while a bit simplistic and sensationalized, is nonetheless a good look at the Cordoban golden age, and a really good read too.

Trade and Traders in Muslim Spain by Constable looks at later Moorish Iberia from an economic perspective.

On the Christian kingdoms:

Reconquest and Crusade in Medieval Spain by Joseph O'Callaghan is about crusading rhetoric and indulgences and attitudes regarding the Reconquista.

Communities of Violence by David Nirenberg is a really in-depth look at religious tolerance and persecution in late medieval Aragon.

I have way less exposure to prehistoric and Roman Iberia, but some books that come to mind:

Osprey Publishing makes an extensive series of short, illustrated military history books that, while unfortunately lacking foot- or endnotes, are in my opinion quite good. They have one on pre-Roman Iberia called Rome's Enemies 4: Spanish Armies, by Rafael Treviño Martinez.

I also enjoyed Roman Iberia: Economy, Society, and Culture, by Benedict Lowe.

Turns out /u/Sunagainstgold covered like half these, but I'll leave them as I second the recommendations. :-P

By no means a comprehensive list, can give more if you ask for more specific things.