SpainHostels.com

Alberg Centre-Rambles. Nice-looking, new youth-hostel located 100 meters from La Ramblas. Rooms have air conditioning/heat. Reservations by phone/fax/email/online. Open 24-hours. Nice looking, multilingual website.
Book Center-Ramblas Barcelona, Barcelona, Spain with Hostelbookers

Albergue Juvenil Barcelona - Gothic Point. New youth-hostel located on the eastern edge of the Gothic Quarter, near the Juame I metro stop. All rooms have toilet & washbasin, air conditioning & heat. Accepts credit cards. Open 24-hours. Has internet-room onsite! Nice looking, Flash-full, multilingual website.

Itaca Hostel, a backpacker-type youth-hostel, is "located in the heart of Barcelona's Gothic area, in a quiet street opposite the Cathedral." Dormitory rooms of 5,6,& 8 persons. Kitchen, internet in their cafetería, lockers, rentable sheets/towels, other good stuff. CHEAP! Phone/Email for contact on nice, multilingual website.
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Famed youth hostel (youth-hostel = albergue juvenil" in Spanish) located INSIDE the Plaça Reial along La Rambla. This is Spain's largest and most popular "Party Youth-Hostel". Has typical bunk-bed dorm rooms and community bathrooms/showers, game/internet room, open 24-hours, light-sleepers take caution. Fills weeks/months in advance. Cheap!
Book The Kabul Hostel, Barcelona, Spain with Hostelbookers

Alberg Pere Tarrés. Nice looking youth-hostel located outside the old city center, off most maps, but 15-minutes to the center by metro(?). 92-person capacity in several number-person configurations. Reservations by phone/fax/online. Multilingual website.
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Alberque Juvenil Sea Point. This BEACHSIDE youth-hostel is located... ON THE BEACH(!) 10 minutes walk from the Barceloneta. All rooms have air conditioning & heat. Free internet access! Accepts credit cards. Open 24-hours. Nice, Flash-full, bilingual website.

Well-located 1 block from the Placa Reial in the Gothic Quarter. Typical youth-hostel has air conditioning/heat. Reservations online. Bilingual website.
Book Sun and Moon Hostel, Barcelona, Spain with Hostelbookers

Located in the Gothic Quarter ("Barri Gòtic" or "Barrio Gótico"). Rooms have sinks and shared bathrooms in the hall and most rooms have balconies. Guests have access to washing machine and kitchen facilities. Multilingual website.