I was wondering if anybody knows the limit of links that google will accept

Your sitemap is nothing to do with the number of backlinks, that's how many pages your site has. If you're asking how many external links before your site is sandbaxed I've heard 10 a day for the first minth is OK.

 

This is like this, it depends on the competition, if the competition is too high then you have to manage that if there is not so much competition then you have to take few links!