Citilab is in Cornellà, a town next to Barcelona. There are different options to get to the Citilab:
Train:
'Cercanias' (spanish) or 'Rodalies' (catalan), which is a regional train. You will find train stations at Plaça Catalunya, Passeig de Gràcia and Sants Estació. The regional train logo is something like a reversed white 'C' in a red circle. The colored number next to it is the train line. The line to Cornellà is the yellow 4. Then take the tram (T1 or T2) to Fontsanta/Fatjó
Metro. Two lines to get there:
Blue L5 (Diagonal tube station is closest to the town center) gets you to Cornellà (last stop). Then take the tram (T1 or T2) to Fontsanta/Fatjó
Green L3 (Catalunya tube station is closest to the town center) gets you to Maria Cristina station. Then take the tram (T1 or T2) to Fontsanta/Fatjó
All these combinations will take you 35-45 minutes to the venue from town center.
Some resources:
Citilab gmap: http://maps.google.com/maps/ms?f=q&hl=en&q=cornella+barcelona+spain&ie=U...
Barcelona public transport website: tmb.net
Transport maps:
- PUBLIC TRANSPORT MAP: http://www.tmb.net/img/genplano.pdf
- TRAM MAP: http://www.trambcn.com/phtml/admin/fotos/REC/recorregut.pdf
- POCKET PC & PALM MAPS: http://www.tmb.net/en_US/siterelated/tmbmulticanal/tmbmulti.jsp