as everybody alrealy stated, Jane's is probably your best bet if you're looking for specs and that type of info. You might also want to look at the "real" spotters bible...JP
Airline Fleets. This book is basically a directory of all current liscenced commercial aircraft....find registrations, aircraft histories (mfd, del, ex regs) and much more...I would be lost without it! Check out their site: http://www.buchairnet.com/
Never tell your girlfriend about all the 'action' you're getting at the airport - only photogs understand that.