I have made changes in page in the month of september and google didn't scrawl it after 28th September 2009......what's the reason behind it... i have submitted sitemap also in september. Page is www.mandakiniinfertilitycentre.com/eggdonation.htm What could be the reason for this?
The main reason of google not crawling any site is due to the meta tag of NOINDEX or you've tried to spam google,so you may be banned by google.
what is the best way of link building....? If i do blog post .....how many blogs posting i should do...? they all will have 0 PR.... Can i submit particular site page as a signature in forums..? This will once again have 0 PR.... Both options given above will work or not?
I wouldn't worry about PR, as Google will find its way to any PageRank page, and even non-indexed pages, sooner or later. Like everyone else said, link building is the key to getting cached in Google. Some good ways to link build are the common blog commenting, posting on forums with signature links (like DP!), submit articles to article directories, and do guest blog posts on other blogs related to yours with a links in the post (however many the owner will allow). You can try to buy links, but you have to really be careful to spend your money on links which will boost your website's possibility of gaining exposure to good old Google and getting higher SERPs; not buy links which will hurt your website, such as link farms, or links that won't even matter at all, like dropped domains.
there is problem of link building, if you can start it and you will update your web pages regularly then your pages will crawl regularly by search engines.
What I suggest is that, you delete the sitemap and try to re-submit your sitemap then it goes into the queue. Also try making some changes in the content and then pinging google, yahoo, bing, etc. using pinging services like pingoat, pingler, pingomatic, etc.