hi, i have developed a site and its crawled by google. but some data is cached from long and not updated on google for long time say a week or so. how do i tell google that my data is being updated. bcos cached data on google is creating problems for me.
and for data .. i place a tick mark(image) prior to it and i have a alt tage like tick to it. google display this alt tags in description ..how do i prevent this?
There's a setting in Google Webmaster Tools for the "crawl rate" of your site. Set it to "faster".
Also, make your site search-engine/webcrawler-friendly by following Google's guidelines (thanks Pete for the link).
Lastly, if you are linked to by sites with very high (low) pagerank, then your site will be crawled more frequently, or even daily.
There is also some speculation that changing your page titles causes Google to re-crawl your site, and also a more-likely apocryphal suggestion that the Revist-After meta tag is actually used by Google.