Prices range from $25 and way up. Depends on sites they submit to and how many. I say submit your site to search engines yourself then get directories done. You can do some by yourself or pay for it.
If you want best SEO than only use auto submission for Search engine. Directory Submission should do by Manual Work.
My advice is never pay for search engine submissions. They will find you. A few quality inbound links to your site from somewhere like digg.com will see to that. As for directories, there are many people on here who offer good submission services, simply check their reputation before paying up!
I too agree, don't ever pay for search engine submissions. You can check on line for didectory submissions