99% are them are pyramid schemes and MLM (please google if you dont know)
the remaining 1% involves lot of rote labour and like sourabh said they are short term work.
and then there are skill and value based jobs like webdesigning, programming, article writing, webmastering etc... those are genuine and good avenues for people who have good skills.
for legitimate info I suggest you become a member of digitalpoint forum (the number one forum for webmasters) or other popular forums and participate in the discussions... in this way you are bound to learn a lot about online opportunities.
dont ever give your money to others without thinking and researching what are you getting in return. so if you do that thinking and research you can easily classify those home/parttime jobs advertised in paper as bogus
or like a 'dog chasing its own tail' work - you can see something and will work hard in the pursuit of getting it but will wear out eventually.
bottomline: theres nothing called as free lunch 
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