Last time google bot visited my site www.jeepcommander.net was 8 april, i changed lots of things and i want it to visit it again, what do i do? I already tried pinging with pingomatica but didn't work
Ping-o-matic won't cause Google to come to your site. You should submit a sitemap to Google if you haven't. http://www.google.com/webmasters/sitemaps/
Also try adding more pages to the site, I only see the main page. Bot won't come very often if you have only a few pages.
It might be related to the updates, mate... all the weird crap happening. I've noticed in other threads that people have mentioned less frequent visits by google. Sitemaps might help, but it's not a guarantee. But probably the best solution is what alph suggested - if next time googlebot visits it sees the site has grown then it will have more reason to revisit again. it's probably worth adding a new page every 3-7 days, at least. Good luck!