computer crawler for internet

I am not too internet saavy, but have heard about computer crawlers, that post info on various blogs, websites, ect. I am in beta testing mode for my site, and am looking to get users to sign up for free. The problem is getting them to my site...[login to view URL] Is there any software than can mass post info about my site and service on various websites/blogs/ chat rooms, ect. Please let me know. I would be willing to pay some $$$ for help and assistance.