One metre interactive grid (long lat) superimposed on a map

People,

I have done a bit of Googling but am a little overwhelmed about where to 
start - I want to add an interactive 1 sqm grid to the attached plan (I 
have the original as a SVG file but it is too large to attach - I 
imported it from a PDF file) square with longitude and latitude such 
that people could click a rectangle of squares to indicate a proposed 
new building lot on the site.  Is SVG the right tool to build such an 
interactive map for a web page?

Suggestions about where to start looking would be greatly appreciated.

Thanks,

Phil.
-- 
Philip Rhoades

PO Box 896
Cowra  NSW  2794
Australia
E-mail:  phil@pricom.com.au