I'll say few ways to get money from twitting:
Clearly you need twitter account to start with secondly you need to get followers and the best way is to follow other people.
There is 2 nice sites which i use for this http://fastfollowers.com/Start.aspx nice system with credits so they would follow you for sure if the credit offer is good I've used 2-3 credits all time while been there and the second one is http://twitterfollower.com/ made by famous blogger John Chow. At http://twitterfollower.com/ i simply clicked from page 1 to last page in 2 days and got about 800 followers from those two sites.

Now I'll give you few sites to help you with advertising and other great free tools I've used in these few days first and probably the best I've seen/heard http://hootsuite.com and the second one is http://revtwt.com/ They both have pretty clear instructions how to use the site.
There is also Pay Per Tweet site which I'm trying to use but seems like it requires lots of more followers to get offers but the site is http://sponsoredtweets.com/
So there are few great sites to start with and I'd say you shouldn't pay to get followers and you shouldn't need to pay in any of those sites. And be aware cause there is lot of scam sites in google.

I think that's it for this time and I'm going to get more info about twitting too when i get to know it better. I've just started myself and its pretty new to me. I'll keep you guys posted.