A tip regarding the directory listing is whether a directory is found in search results. If it is, especially on Google, take it as a good sign.
I have found plenty of directories where their home page is in Google & they have blocked Googlebot from crawling the rest of their directory.
I always check to see if Google has a cache of the page in the directory I want to submit my link to. If it does not then I don't bother as the directory owner has probably blocked the search engines' spiders & the link will not get found.
If you have the Google Toolbar it is very easy to see if a page is cached. Click on the drop down next to the 'Page Rank' & select 'Cached snapshot of page'.
If you do not have the Google Toolbar in your browser I recommend you download it.
If you know HTML check the code of the page you want your site on to make sure that there is not:
- A robots noindex tag in the header
- The links are not rel="nofollow"
- The link is Javascript or some other script
* Don't submit to too many directories too fast. Space it out over several months.
Wise words. Don't submit to more than about 10 - 20 per week. If Google finds a sudden rush of links to your site then that is a pattern they have found that spammers use & you might find your pages being lumped in with them.
It's usually worth the money to buy a link from that directory.
* Avoid free directories.
Personally I disagree with those statements. In my experience I have found that many pay directories are just as full of spam & as worthless as some free ones.
And I have found plenty of free directories that contain good content as the owner takes the time to check that submitted sites are not spammy or other bad types of sites.