I started a directory and was gettting no submissions the first couple of days so i decided to make regular links free to see if I could get some links in there. After leaving it like that for a day I got 330 submissions. The websites were about a wide variety of subjects. I decided to change links to $1.25 to be able to catch up with all the submissions. My question is how can I check to see if this was spam or genuine submissions?
You could check your log files for the source IP addresses ... To be honest ... if the sites are good and the email addresses are valid ... who cares where they came from? You can drive yourself crazy trying to figure out the motives of every webmaster that submits a site. Create a set of guidelines for the type and quality of sites you are willing to accept ... then stick to them.
put a filter on known spam words on your submission form, so you dont have to go through all the junk stuff..