The best archaeological guide to Israel is now out in its fifth edition.  The Holy Land: An Oxford Archaeological Guide, by Jerome Murphy-O’Connor is the best companion for a trip to ancient sites anywhere in Israel.  The section on Jerusalem is especially lengthy (150 pages in the 4th edition), and the whole is accurate and readable.  Don’t expect to find out about hotels or restaurants – this is a guide to archaeological sites only!  The 4th edition came out in 1998, so while I haven’t yet seen the new edition, I expect it will have significant updates.  The author has lived in Jerusalem longer than I have been alive.