Check by search.yahoo.com link:www.domainame.com Google updates backlinks once 3-4 months and anyway shows just 3-5% of the total number ...
It depends on the sites you are posting to, if you are leaving irrelevant comments on blogs, many of the admins won't allow it, and your site might be quickly blacklisted amongst bloggers
Best way to get backlinks is to do article marketing. Sure it takes some time but it's worth the effort
Wait man .. then check your backlinks with yahoo site explorer. You have to be patient .. it's not like you'll see the backlinks overnight
well what kind of links do you have you should give us some ideas so we can check and tell u the reason maybe its a no follow link