Look in men's magazines or local papers for positions. You can usually see listings in the back pages.
This is a really good site-http://www.sexyjobs.com/phonesex.asp
You also might be interested in text chat-http://www.text121chat.com/
KEEP IN MIND:
1. NEVER pay to work. If the company asks for any form of investment, run away as fast as you can. It's probably a scam. You should not have to put a down payment or anything towards working for someone else.
2. ALWAYS be sure to ask if your number is protected. They should have double or triple coding which means your clients have no way of calling your real number.
3. Be sure to check and see what happens if the job doesn't work out. For example, what if you try it for three weeks then hate it - can you just quit? Read the fine print in detail before you sign anything.
4. Before signing up with any company find out what and when pay is. Keep accurate track of all of your calls and other info. Be sure to know any payment triggers ahead of time (i.e - you must earn $25 before you get a check by mail, etc)