With the large number of productions ongoing, there are many companies that provide support services to film shoots. A great resource for finding film related services is the Barcelona Film Comission. Various companies offer equipment rental services. Below is a list of rental houses.
http://www.masquevideo.com/ (rental house focussed on video production and broadcasting)
http://www.tacticalmovies.com/ (production company specialized in weaponry, police/army clothing and trained extras)