Search Engine Submission Tutorial:

Search engines or directories don't like computer programs that submit pages to them. I think it's because many uneducated users don't know how to use the software, and are submitting pages to unrelated categories, unrelated search engines or foreign language search engines. The administrators of those directories need to go through thousands of unrelated or foreign language sites and delete them one by one
(very time consuming).

Google says:
"Don't use unauthorized computer programs to submit pages, check rankings, etc. Such programs consume computing resources and violate our terms of service. Google does not recommend the use of products such as
WebPosition Gold that send automatic or programmatic queries to Google."

Google Webmaster Guidelines
http://www.google.com/webmasters/guidelines.html

I doubt that SubmitWolf is on Google's list of unauthorized programs. However, automatic site submission is not necessarily the most productive way to achieve listings that help your Google page rank.
Automatic submission programs may submit your site to multiple directories, but unless these directories are examined individually, you can't know if you've chosen the best category for -that- particular directory.
Human oversight is much better, even if a bit slower. By
manually submitting your site, you have a chance to examine the directory structure, choose which page your link appears on, and optimize your keywords and description for that particular directory and its users. Choosing a subcategory with fewer outbound links, or a
related category that is highly popular with the directory's users, can not only increase traffic from that source, but can also contribute to the amount of page rank 'given' by the linking site.

Submitting website too often

Some search engines have a No-Spam rule. If they receive the same submission often, in a short period of time, they might reject your submission or give you a lower ranking.

Directories:
http://dmoz.org  - Open Directory is the best free directory. The biggest directories have quite high page rank.

Second most important directory is Yahoo, but it costs $299 to be included: http://dir.yahoo.com

Google does have an "Add URL" submission page, which you can find here: http://www.google.com/addurl.html

Submitting to search engines is only one little piece of the puzzle. If you want your business to grow you need to spend some money on advertising. The only serious methods I use and recommend are eBay, Google ads, and Overture.

List of directories for free submitting