the urban design students at columbia just spent time there and are now focusing on barcelona as a studio project. you may want to see what they're up to.

here are some sites about urban planning in Barcelona, and L'Eixample and Gràcia districts specifically... I'm afraid most are not in english but do have some graphic material (photos, maps) that maybe will help you:

since some years ago the City Council has started to free the inner courts of most blocks of L'Eixample, this site is quite good, it will show you which ones are recuperated and which will be returned to the original Cerdà conception (click on Block Interiors):
www.proeixample.com/eng/

check out the City council's official site for the Eixample district and the Gràcia districts:
www.bcn.es/districtes/

also, the Urbanism official site (click on Informació Urbanística for gettin' the Metropolitan General Plan, the City Guide with all the streets and particular info on some urban projects):
www.bcn.es/urbanisme/

I did a compilation of buildings of L'Eixample district, from Modernistes to contemporary projects, in this message of another forum:
www.skyscrapercity.com/showthread.php?t=177546

the Barcelona Metropolis Mediterrània is an interesting on-line magazine -published by the City Council- about urban space and the transformations of Barcelona, there are tons of numbers and are in english, you may want to spend some time looking for particular articles about Gràcia and L'Eixample ... I think I've read some time ago some things about both districts but can't recall which numbers (click on english, then for finding the old numbers click on Archive):
www.bcn.es/publicacions/b_mm/bmm60/index.htm

also you could try to find projects in the Quaderns magazine, edited by the Catalan Official College of Architects:
quaderns.coac.net/q/index.html

and the INDE magazine archives, also edited by the COAC (though these are in catalan only):
www.coac.net/inde/

some more about L'Eixample district:
es.wikipedia.org/wiki/Ensanche_de_Barcelona

the New York to Europe Planning Delegation for the reconstruction of the WTC site visited 5 cities, among them Barcelona, its not focused on any particular district but maybe you'll be interested (PDF):
www.picced.org/pubs/europedelegation.pdf

about Gràcia squares (in catalan but with pics):
www.gracianet.org/la_vila/tomb/

if you're interested in statistics of Barcelona, you could try to contact the DIBA, which is the provincial government of BCN's metro area:
www.diba.es/cartosig/cartoprov.asp

lots of historical plans of L'Eixample and the growing process of Barcelona in this PDF:
www.ub.es/escult/lonas/intro.pdf

the World-Wide Web Virtual Library on Landscape Architecture features some Barcelona projects:
www.clr.utoronto.ca/VIRTUALLIB/LARCH/proj.html

this student's site has some things about art in/and public spaces of Barcelona:
www.spaindev.pomona.edu/barcelona/

about L'Eixample:
www.geographyfieldwork.com/Eixample.htm
www.planum.net/4bie/main/m-4bie-barcelona.htm

a site about public transport in BCN:
es.geocities.com/areaBCN_2005/inicio.htm

hope this can help..

this is what david jaubert pointed at, surely could be very interesting: Urban Design Studio III

wow medit, thanks for all the links, they should be very helpful.

The latest version of Arch Record has an article that talks about it.

you may also may find some interesting stuff in the FAD site...

and 2003 was the Design Year (Any del Disseny) in Barcelona (after the 2002, which was the Gaudí Year): www.adb2003.org/
there are some curious things like a competition, called Racons Públics (Public Corners) (only in catalan), not only for architects or designers but also open to the general public about the design of Barcelona's urban spaces, promoted by the FAD organization, the City Council and a newspaper

if I remember more sites I'll add them later...

does someone (from Columbia or wherever) know why I can't have access to the Urban Design Studio III student's work, while the other studios from Spring 2005 show some work already? ..
I'm curious to see what came out of the 'Re-Centering Barcelona' experience..

I spent 6 months in Barcelona, absolutely loved it. I dont know much about Gracia's public spaces but in the Eixample and the Raval I know of a lot. As for bars, that is one thing i know. If you like to club, you cant beat Space Barcelona. Its on Calle Tarragona. Take the metro to Tarragona, get out and its right in front of you. For bars, one of my favorites was London Bar right off Las Ramblas on Nou de la Rambla. Tucked away back in that area too is Moog, a pretty cool, very small dance bar. All the bars at the beach are okay, just too touristy for my taste. La Paloma is really cool as well. Have fun in Barcelona!