I would use LiveJasmin, there are dozens and dozens of really pretty models there and many of them have really long hair.

For instance:

jasmin.com/free/chat/BestErika?category=&psid=mardux&pstool=202_1&psprogram=revs&campaign_id=79733

and

jasmin.com/free/chat/AngelOfSky?category=&psid=mardux&pstool=202_1&psprogram=revs&campaign_id=79733

Here's a selection of some of the girls:

kinkyforums.com/cams

your questions:

- which website is the safest?

Don't know which one is safest, but def. go with the bigger / better known ones like LiveJasmin

- how do the transactions work? If i become a member , can the website charge my credit card anytime they want?

They don't charge your credit card without your knowledge. I don't think they've got a recurring plan, so when your credits run out, you can buy new ones. Also you get bonus credits when you first sign on.

- Will my credit card information be at risk if I become a member.

Not more than with any other (online) company you hand your cc info to.

- Which website has the most long haired girls?

I found a ton of girls on Jasmin. Also I find that the site works a lot smoother than others I've tried.

- Which website is more economical?

You can start out with a free account, but most of the girls don't do much if you don't give them any credits.