find one vector-file among thousands?

You can convert all the vector files to sites files of the same or similar
name, then zoom into your lake and use d.sites.qual -n which outputs the
number of sites drawn in the current region. You can put it in a loop and
echo the filename, then look at the output for the one with the most sites
displayed, e.g.:

cd $LOCATION/dig
foreach i ( lakes* )
v.to.sites -a $i out=$i.s
end

d.zoom to your lake

cd $LOCATION/site_lists
foreach i ( lakes*.s )
if ( `d.sites.qual -n $i` > 0 ) then
echo FOUND IT $i
endif
end

- Bill