Steemnow.com is a handy site for calculating how much your upvote is worth , you will also have seen that you have an upvote % that you can set , but only once your Steam Power (SP) reaches 500 SP. So if your SP is under a 100 SP your 100% vote is worth nothing , yip zilch and until you reach 100SP it stays like that .
When you reach 100SP (you can just buy SP) finally and thats gonna take quite a few months for most new steemians your 100% vote is 0.001 steem , 200SP your 100% vote is worth 0.002 Steem and so on ...
The most important site to learn for new steemians is http://steemd.com just add /@yournamehere to the address and you can find your voting power and SP score and all the data accociated with your account
PS you can also see how your reputation is doing the score has a decimal place like 25.6 or something