Tickets to see the Foos are available on ticketmaster for tonights concert.
I went to see them last night and they were FANTASTIC! Dave mentioned they were going to do another gig in the UK soon, so I went to register for an alert on ticketmaster and found tickets were available for tonight - standing and seated at £32.50 (the seats seem to be on the upper tier but close to the stage. The end stage was an open lay out and seemed visible in the blocks to the very side of the stage. Also nearly half the concert was performed on a stage in the centre of the arena.
I don't know how these have come about as they were showing as sold out very soon after they went on sale.
Hope this is useful to a FOOS fan. Great if you live in the area.