>I've heard in other forums that it's good to resubmit your URL to search engines once a month in order to keep a good place on their listing.
And which submission service were they pushing?
>Can resubmitting that often backfire and be looked at negatively by the search engines...resulting in a worst listing?
It can backfire ... I only resubmit if I've done a major upgrade to the
site or remodelled the structure. Some of the search indexes give higher
precedence to older sites, some to more recently submitted sites. But no one
is certain which ones are which.
See this page ... it's the current state of the rumor mill.
http://members.tripod.com/~maximaniac/botrumor.htm