Should I pay for a service to submit my site to search engine directories?

You shouldn't pay for a service to submit your site to search engines!

It makes no sense to spend money on that, especially because many of these services are "scams". They will take your money and won't submit your site, and even when they submit it, many of them use submission programs that are rejected by search engines.

After your site is "ready", submit it to the search engines by yourself!