The 2009 edition is only available in Limited Preview through Google Search, to protect Rick's copyright rights. If you access that edition online more than a limited # of pages, it will cut off your access. So that's not going to work for what you need.
What I'd suggest is contacting the Rick Steves staff, click Contact Us below and send a msg to them or faster to phone them, and ask at which Rome stores the book is sold, if any, they'll know (there a limited demand for travel books in English, in Rome). This will save you from wasting the time running around Rome to all the English book stores and maybe not finding one in the end.