CORDE: a searchable corpus based on texts dating from the very earliest up until almost the present day. It is possible to narrow down a search to the medieval period using the date selection option
DIALNET: ' el servicio de alertas documentales que le permite estar al día de la producción científica en lengua española'. This includes the humanities and there is a searchable database
Diccionario de la lengua española: in addition to giving definitions, it also gives the conjugation of each verb if you click on the blue square beside that verb
Philobiblon: database of manuscripts, subdivided into:
BITAGAP / Bibliografia de Textos Antigos Galegos e Portugueses
BITECA / Bibliografia de Textos Antics Catalans, Valencians i Balears
Repertorio de medievalismo hispánico (Recoge la labor científica de los estudiosos españoles y portugueses y de los investigadores hispanistas y lusistas sobre temas hispánico-medievales (400-1525). La obra iniciada y dirigida por D. Emilio Sáez, se publicó en cuatro volúmenes, correspondientes a los años 1955-1975/1985. Actualmente, continúan las tareas de actualización)
A number of books on hunting, including some by Don Juan Manuel
Medical texts from the Hispanic Seminary of Medieval Studies
There are many, many more primary texts at the Biblioteca Virtual Miguel de Cervantes, including the Auto de los Reyes Magos, Libro de Alexandre, works by Fray Íñigo de Mendoza, Juan del Encina, Fernando del Pulgar, Pedro López de Ayala, Juan Rodríguez del Padrón and Gómez Manrique’s La Representaçión del Nasçimiento de Nuestro Señor
Cahiers d'Études Hispaniques Médiévales (formerly Cahiers de linguistique hispanique médiévale). Volumes from 1976 onwards are available to be read online and as pdf documents.
Celestinesca can also be searched via Compludoc. Volumes 1-26 are available as free pdfs. There is the option of downloading individual articles or complete volumes.
En la España medieval. Individual essays from volume 1 (1980) onwards are available for download as free pdfs.
La-Celestina, ‘Lista de correo electrónico para el estudio de La Celestina’
Mediber, ‘an on-line discussion list (accessible via Internet) devoted to all aspects of Medieval Iberian Literatures, Languages, History, and Cultures’