Pinecone research, Surveysavvy, Greenfieldonline, Yahoo are some of the larger survey companies, who pay regularly . A list of companies you can join for free , with details of payments, is available at http://www.pcworkathome.net/onlinepaidsurveys.html

yeah it is legit if you get pay. If you interested in a program I would suggest trying Cashcrate. I have made about $55 in two week on the site. The blog below detail the program and cash incentives

http://needpocketcash.blogspot.com/

They're not worth it. You WILL need to give your personal info to them to get paid. The ones that are legitimate are usually looking for very specific requirements for each of their surveys (a specific profession, age range, hobbies, items purchased recently, etc.) If you happen to fall into the exact category they're looking for, they'll have you fill out a survey for a tiny amount of money or a chance for a bit more money or prizes. They may only send you a survey once every couple weeks.

You'll ultimately put in a lot of time for very little money. If you have nothing else better to do, go for it. But if you value your time, there are better and faster ways of making money.

P.S. A good sign of someone trying to scam you on Y!A is a blank avatar picture, very few questions answered, and 0% best answer (i.e. most of the people answering this question).