I found some relevant keywords but the monthly hits are 1000 or less. What would be the minimum number of hits I should see in a keyword before I consider it worth the effort?
I think that really depends on what you're trying to sell/promote. If it's a high ticket item, and the "popular" keywords are very competitive, I'd try the more obscure ones. I've also found that running brief Adwords campaigns gives you a much more accurate number as to how many hits there are for a certain keyword (since you get to see impressions for your ad).
Thats a cool idea to find the exact hits to a website. this information is also reliable since its coming from google website. Also google analytics should do the trick..
dont care about how many search hits a month, coz if u have good content and do proper seo all ur posts will pick up its own keywords and not jus the one in ur url .